fuel injection FORD SIERRA 1993 2.G Engine Electrical Systems Workshop Manual
[x] Cancel search | Manufacturer: FORD, Model Year: 1993, Model line: SIERRA, Model: FORD SIERRA 1993 2.GPages: 24, PDF Size: 0.93 MB
Page 1 of 24

System type
1.3 litre models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Bosch inductive discharge system
1.6 litre models (except Economy) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Bosch inductive discharge system
1.6 litre Economy models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ESC system with Lucas “Hall effect” distributor
1.6 litre CVH (R6A type) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Distributorless controlled by EEC IV system
1.8 litre SOHC models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ESC II system with Bosch “Hall effect” distributor
1.8 litre CVH models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ESC Hybrid system
1.8 litre CVH (R6A type) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Distributorless controlled by EEC IV system
2.0 litre SOHC carburettor models up to 1985 . . . . . . . . . . . . . . . . . . . . Bosch inductive discharge system
2.0 litre SOHC carburettor models from 1985 (except P100) . . . . . . . . . ESC II system with Bosch “Hall effect” distributor
2.0 litre DOHC carburettor models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ESC II system
P100 models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Bosch inductive discharge system
2.0 litre SOHC fuel injection models up to 1987 . . . . . . . . . . . . . . . . . . EEC IV system with Motorcraft “Hall effect” distributor
2.0 litre SOHC fuel injection models from 1987 . . . . . . . . . . . . . . . . . . . EEC IV system with Bosch “Hall effect” distributor
2.0 litre DOHC fuel injection models . . . . . . . . . . . . . . . . . . . . . . . . . . . EEC IV system
Coil
All models except CVH (R6A type) and 2.0 litre DOHC
Output (minimum) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25.0 kilovolts
Primary winding resistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.72 to 0.88 ohm
Secondary winding resistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4500 to 7000 ohms
1.6 and 1.8 litre CVH (R6A type)
Output (minimum) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37.0 kilovolts
Primary winding resistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.50 ± 0.05 ohms
2.0 litre DOHC carburettor model
Output (minimum) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25.0 kilovolts
Primary winding resistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.72 to 0.88 ohms
Secondary winding resistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4500 to 8600 ohms
2.0 litre DOHC fuel injection model
Output (minimum) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30.0 kilovolts
Primary winding resistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.72 to 0.88 ohms
Secondary resistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4500 to 8600 ohms
Distributor
Direction of rotor arm rotation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Clockwise
Firing order . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1- 3 - 4 - 2 (No 1 cylinder nearest timing cover)
Dwell angle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Automatically controlled by electronic module (not adjustable)
Chapter 5
Engine electrical systems
Alternator - testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
Alternator - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
Alternator brushes - removal, inspection and refitting . . . . . . . . . . . . .7
Alternator drivebelt(s) - checking, renewal and tensioning . . . . . . . . . .5
Battery - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
Battery - testing and charging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
Coil - testing, removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . .12
Distributor (OHC models) - removal and refitting . . . . . . . . . . . . . . . .15
Distributor cap and rotor arm (OHC models) - removal and refitting .13
Distributor components (CVH models) - removal and refitting . . . . . .14
EEC IV system components - removal and refitting . . . . . . . . . . . . . .21Electronic modules - removal and refitting . . . . . . . . . . . . . . . . . . . . .18
ESC Hybrid system components - removal and refitting . . . . . . . . . .20
ESC II system components - removal and refitting . . . . . . . . . . . . . .19
General information and precautions . . . . . . . . . . . . . . . . . . . . . . . . . .1
Ignition timing - adjustment for use with unleaded petrol . . . . . . . . .17
Ignition timing (OHC models) - adjustment . . . . . . . . . . . . . . . . . . . .16
Starter motor - brush renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
Starter motor - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . .8
Starter motor - testing in the vehicle . . . . . . . . . . . . . . . . . . . . . . . . . .9
Spark control system components - removal and refitting . . . . . . . .22
Spark plugs and HT leads - removal, inspection and refitting . . . . . .11
5•1
Specifications Contents
5
Easy,suitable for
novice with little
experienceFairly easy,suitable
for beginner with
some experienceFairly difficult,
suitable for competent
DIY mechanic
Difficult,suitable for
experienced DIY
mechanicVery difficult,
suitable for expert
DIY or professional
Degrees of difficulty
Page 2 of 24

Ignition timingLeaded petrolUnleaded petrol
(at idle with vacuum pipe disconnected)(4-star, 97 RON)(Premium, 95 RON)
Early “Economy” models (800 rpm - vacuum pipe connected) . . . . . . .16º BTDC12º BTDC
1.3 litre models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12º BTDC8º BTDC*
1.6 litre models with VV carburettor . . . . . . . . . . . . . . . . . . . . . . . . . . . .12º BTDC8º BTDC*
1.6 litre models with 2V carburettor . . . . . . . . . . . . . . . . . . . . . . . . . . . .10º BTDC6º BTDC†
1.8 litre SOHC models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10º BTDC6º BTDC†
1.8 litre CVH models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .ESC Hybrid controlled, no adjustment possible
2.0 litre carburettor models up to 1985 . . . . . . . . . . . . . . . . . . . . . . . . .8º BTDC4º BTDC*
2.0 litre carburettor models from 1985 (except P100) . . . . . . . . . . . . . .10º BTDC6º BTDC†
P100 models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6º BTDC2º BTDC†
2.0 litre fuel injection models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12º BTDC8º BTDC†
*Fill with leaded petrol (4-star, 97 RON) every 4th tankful
†Not all vehicles are suitable for continuous operation on unleaded petrol.
Spark plugs
Make and type:
All models except 1.8 CVH, CVH (R6A), 2.0 DOHC and P100 . . . . . . . .Champion RF7YCC or RF7YC
1.8 CVH engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Champion RC7YCC or RC7YC
P100 model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Champion RF7YC or F7YC
1.6 and 1.8 CVH (R6A type) and 2.0 DOHC . . . . . . . . . . . . . . . . . . . . . .Champion RC7YCC
Electrode gap:
Champion F7YCC or RC7YCC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .0.8 mm (0.032 in)
Champion RF7YC, F7YC or RC7YC . . . . . . . . . . . . . . . . . . . . . . . . . . . .0.7 mm (0.028 in)
Note: The electrode gap above is the figure quoted by Champion for use with their recommended spark plugs. If plugs of any other type are fitted,
refer to their manufacturer’s gap recommendations.
HT leads
All SOHC models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Champion LS-09 or LS-10 boxed set
1.8 CVH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Champion LS-10 boxed set
1.6 and 1.8 CVH (R6A type) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Champion LS-30 boxed set
2.0 DOHC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Champion LS-29 boxed set
Maximum resistance per lead . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30 000 ohms
Alternator
Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Bosch, Lucas, Motorola, or Mitsubishi
Regulated output voltage at 4000 rpm (3 to 7 amp load) . . . . . . . . . . . .13.7 to 14.6 volts
Minimum brush length:
All alternator types except Motorola . . . . . . . . . . . . . . . . . . . . . . . . . .5.0 mm (0.20 in)
Motorola type alternators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4.0 mm (0.16 in)
Starter motor
Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Pre-engaged; Bosch, Cajavec, Lucas, or Nippondenso
Minimum brush length:
All except Bosch long frame 1.1 kW and JF, and Nippondenso . . . .8.0 mm (0.32 in)
Bosch long frame 1.1 kW and JF, Nippondenso starter motors . . . .10.0 mm (0.40 in)
Battery charge condition:
Poor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12.5 volts
Normal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12.6 volts
Good . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12.7 volts
Torque wrench settingsNmlbf ft
Spark plugs:
SOHC models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20 to 2815 to 21
CVH models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18 to 3313 to 24
DOHC models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15 to 2111 to 15
Crankshaft speed/position sensor clamp bolt (ESC Hybrid system) . . .4 to 73 to 5
Crankshaft speed/position sensor screw (DOHC) . . . . . . . . . . . . . . . . .3 to 52 to 4
Camshaft sprocket bolt (CVH models) . . . . . . . . . . . . . . . . . . . . . . . . . .95 to 11570 to 85
Air charge temperature sensor (CVH-R6A and DOHC) . . . . . . . . . . . . .20 to 2515 to 18
Engine coolant temperature sensor (CVH-R6A and DOHC) . . . . . . . . . .20 to 2515 to 18
Fuel temperature sensor (DOHC injection) . . . . . . . . . . . . . . . . . . . . . . .8 to 116 to 8
Alternator adjustment bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21 to 2815 to 20
Alternator mounting bolts:
With coloured patch on threads . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41 to 5130 to 38
Without coloured patch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20 to 2515 to 18
5•2Engine electrical systems
Page 3 of 24

General information
The electrical system is of the 12 volt
negative earth type, and consists of a 12 volt
battery, alternator with integral voltage
regulator, starter motor and related electrical
accessories, components and wiring. The
battery is of the low maintenance or
maintenance-free “sealed for life” type and is
charged by an alternator which is belt-driven
from the crankshaft pulley. The starter motor
is of the pre-engaged type, incorporating an
integral solenoid. On starting the solenoid
moves the drive pinion into engagement with
the flywheel ring gear before the starter motor
is energised. Once the engine has started, a
one-way clutch prevents the motor armature
being driven by the engine until the pinion
disengages from the flywheel.
The ignition system is responsible for
igniting the air/fuel mixture in each cylinder at
the correct moment in relation to engine
speed and load. A number of different ignition
systems are fitted to models within the
Sierra/P100 range, ranging from a basic
breakerless electronic system to a fully
integrated engine management system
controlling ignition and fuel injection systems.
The ignition system is based on feeding low
tension voltage from the battery to the coil
where it is converted to high tension voltage.
The high tension voltage is powerful enough
to jump the spark plug gap in the cylinders
many times a second under high compression
pressures, providing that the system is in
good condition. The low tension (or primary)
circuit consists of the battery, the lead to the
ignition switch, the lead from the ignition
switch to the low tension coil windings
(terminal + /15) and also to the supply terminal
on the electronic module, and the lead from
the low tension coil windings (terminal -/1) to
the control terminal on the electronic module.
The high tension (or secondary) circuit
consists of the high tension coil windings, the
HT (high tension) lead from the coil to the
distributor cap, the rotor arm, the HT leads to
the spark plugs, and the spark plugs.
The system functions in the following
manner. Current flowing through the low
tension coil windings produces a magnetic
field around the high tension windings. As the
engine rotates, a sensor produces an
electrical impulse which is amplified in the
electronic module and used to switch off the
low tension circuit.
The subsequent collapse of the magnetic
field over the high tension windings produces
high tension voltage which is then fed to the
relevant spark plug via the distributor cap and
rotor arm. The low tension circuit is
automatically switched on again by the
electronic module, to allow the magnetic field
to build up again before the firing of the next
spark plug. The ignition is advanced and
retarded automatically to ensure that thespark occurs at the correct instant in relation
to the engine speed and load.
To improve driveability during warm-up
conditions and to reduce exhaust emission
levels, a vacuum-operated,
temperature-sensitive spark control system is
fitted to certain vehicles.Inductive discharge system
This is the least sophisticated system fitted
to the Sierra/P100 range, and comprises a
breakerless distributor and an electronic
switching/amplifier module in addition to the
coil and spark plugs.
The electrical impulse which is required to
switch off the low tension circuit is generated
by a magnetic trigger coil in the distributor. A
trigger wheel rotates within a magnetic stator,
the magnetic field being provided by a
permanent magnet. The magnetic field across
the two poles (stator arm and trigger wheel) is
dependent on the air gap between the two
poles. When the air gap is at its minimum, the
trigger wheel arm is directly opposite the
stator arm, and this is the trigger point. As the
magnetic flux between the stator arm and
trigger wheel varies, a voltage is induced in
the trigger coil mounted below the trigger
wheel, and this voltage is sensed and then
amplified by the electronic module and used
to switch off the low tension circuit. There is
one trigger wheel arm and one stator arm for
each cylinder (4).
The ignition advance is a function of the
distributor and is controlled both mechanically
and by a vacuum operated system. The
mechanical governor mechanism consists of
two weights which move out from the
distributor shaft as the engine speed rises due
to centrifugal force. As they move outwards,
they rotate the trigger wheel relative to the
distributor shaft and so advance the spark.
The weights are held in position by two light
springs and it is the tension of the springs
which is largely responsible for correct spark
advancement.
The vacuum control consists of a
diaphragm, one side of which is connected
via a small bore hose to the carburettor or
inlet manifold and the other side to the
distributor. Depression in the inlet manifold
and/or carburettor, which varies with engine
speed and throttle position, causes the
diaphragm to move, so moving the baseplate
and advancing or retarding the spark. A fine
degree of control is achieved by a spring in
the diaphragm assembly.
ESC (Electronic Spark Control) system
This system is only fitted to early
“Economy” models, and comprises a “Hall
effect” distributor, and an ESC module, in
addition to the coil and spark plugs.
The electrical impulse which is required to
switch off the low tension circuit is generated
by a sensor in the distributor. A trigger vane
rotates in the gap between a permanent
magnet and the sensor. The trigger vane has
four cut-outs, one for each cylinder. When
one of the trigger vane cut-outs is in line with
the sensor, magnetic flux can pass betweenthe magnet and the sensor. When a trigger
vane segment is in line with the sensor, the
magnetic flux is diverted through the trigger
vane away from the sensor. The sensor
senses the change in magnetic flux and sends
an impulse to the ESC module, which
switches off the low tension circuit.
The ignition advance is a function of the
ESC module and is controlled by vacuum. The
module is connected to the inlet manifold by a
vacuum pipe, and a transducer in the module
translates the vacuum signal into electrical
voltage. From the vacuum signal, the ESC
module determines engine load, and engine
speed is determined from the interval
between impulses supplied by the distributor
sensor. The module has a range of spark
advance settings stored in its memory, and a
suitable setting is selected for the relevant
engine speed and load. The degree of
advance can thus be constantly varied to suit
the prevailing engine speed and load
conditions.
ESC II (Electronic Spark Control II)
system
1.8 and 2.0 litre SOHC carburettor models
This system is a development of the ESC
system described previously in this Section,
but it enables more accurate control of engine
operation due to the inclusion of additional
monitoring features and control outputs.
Vehicles fitted with the ESC II system have an
electric inlet manifold heater which warms the
air/fuel mixture when the engine is cold, thus
reducing the amount of fuel enrichment
required, lowering fuel consumption and
improving driveability when the engine is cold.
The heater is operated by the ESC II module
receiving information on the engine temperature
from an engine coolant temperature sensor
mounted in the inlet manifold.
On 2.0 litre SOHC models, the ESC II
module operates a carburettor stepper motor
to control the engine idle speed. Using
information on engine speed, load,
temperature and throttle position (supplied by
a switch on the carburettor), the module
operates the stepper motor to maintain a
constant idle speed. On models equipped
with automatic transmission and/or air
conditioning, additional inputs are supplied to
the module to allow it to operate the stepper
motor to compensate for the additional engine
load imposed by the automatic
transmission/air conditioning. The ESC II
module also operates a “power hold” relay
which allows the stepper motor to function
briefly after the ignition has been switched off
in order to perform an anti-run-on and
manifold ventilation cycle.
2.0 litre DOHC carburettor models
A development of the ESC II system is used
to control the operation of the engine. The
module receives information from a
crankshaft speed/position sensor (similar to
that described for the ESC Hybrid system),
except that the sensor is activated by a
toothed disc on the rear of the crankshaft,
inside the cylinder block), and an engine
coolant temperature sensor.
1General information and
precautions
Engine electrical systems 5•3
5
Page 4 of 24

The ignition advance is a function of the
ESC II module, and is controlled by vacuum.
The module is connected to the carburettor
by a vacuum pipe, and a transducer in the
module translates the vacuum signal into an
electrical voltage. From the vacuum signal,
the module determines engine load; engine
speed and temperature are determined from
the crankshaft speed/position sensor and the
engine coolant temperature sensor. The
module has a range of spark advance settings
stored in its memory, and a suitable setting is
selected for the relevant engine speed, load
and temperature. The degree of advance can
thus be constantly varied to suit the prevailing
engine speed and load conditions.
ESC Hybrid (Electronic Spark Control
Hybrid) system
This system is fitted to 1.8 CVH models,
and comprises various sensors and an ESC
Hybrid module, in addition to the coil and
spark plugs. The distributor serves purely to
distribute the HT voltage to the spark plugs
and consists simply of a rotor arm mounted
directly on the end of the camshaft, and a
distributor cap.
The electrical impulse which is required to
switch off the low tension circuit is generated
by a crankshaft speed/position sensor which
is activated by a toothed wheel on the
crankshaft. The toothed wheel has 35 equally
spaced teeth with a gap in the 36th position.
The gap is used by the sensor to determine
the crankshaft position relative to TDC (top
dead centre) of No 1 piston.
Engine load information is supplied to the
ESC Hybrid module by a vacuum transducer
within the module which is connected to the
inlet manifold by a vacuum pipe. Additional
inputs are supplied by an inlet
manifold-mounted engine coolant temperature
sensor, and an air charge temperature sensor
mounted in the base of the air cleaner. The
module selects the optimum ignition advance
setting based on the information received from
the various sensors. The degree of advance
can thus be constantly varied to suit the
prevailing engine conditions.
In addition to the ignition circuit, the module
also controls an electric choke heater, and a
solenoid valve which in turn controls a throttle
damper on the carburettor. The electric choke
heater is operated by the module using
information supplied by the engine coolant
temperature sensor. The heater is used to
slow down the rate at which the choke comes
off, thereby improving driveability and overall
fuel consumption when the engine is cold. The
solenoid valve controls the vacuum supply to
the carburettor throttle damper. The throttle
damper prevents sudden closing of the throttle
during deceleration, thus maintaining
combustion of the air/fuel mixture which
reduces harmful exhaust gas emissions.
Note that there is no provision for
adjustment of ignition timing with the ESC
Hybrid system.
EEC IV (Electronic Engine Control IV)
system
2.0 litre SOHC fuel injection models
This system controls both the ignition and
fuel injection systems. The EEC IV module
receives information from a “Hall effect”
distributor sensor (similar to that described
previously in this Section for the ESC system),
an engine coolant temperature sensor
mounted in the inlet manifold, a throttle
position sensor, and an air flow meter.
Additionally, on models equipped with
automatic transmission and/or air
conditioning, additional inputs are supplied to
the module to allow it to raise the idle speed
to compensate for the additional engine load
imposed by the automatic transmission/air
conditioning. The module provides outputs to
control the fuel pump, fuel injectors, idle
speed, and ignition circuit. Using the inputs
from the various sensors, the EEC IV module
computes the optimum ignition advance, and
fuel injector pulse duration to suit the
prevailing engine conditions. This system
gives very accurate control of the engine
under all conditions, improving fuel
consumption and driveability, and reducing
exhaust gas emissions. A “limited operation
strategy” (LOS) means that the vehicle is still
driveable, albeit at reduced power and
efficiency, in the event of a failure in the
module or its sensors.
2.0 litre DOHC fuel injection models
A development of the EEC IV system is
used to control both the ignition and fuel
injection systems. The module receives
information from a crankshaft speed/position
sensor (similar to that described for the ESC
Hybrid system), except that the sensor is
activated by a toothed disc on the rear of the
crankshaft, inside the cylinder block), a
throttle position sensor, an engine coolant
temperature sensor, a fuel temperature
sensor, an air charge temperature sensor, a
manifold absolute pressure (MAP) sensor, and
a vehicle speed sensor (mounted on the
gearbox). Additionally, on models with a
catalytic converter, an additional input is
supplied to the EEC IV module from an
exhaust gas oxygen (HEGO) sensor. On
models with automatic transmission,
additional sensors are fitted to the
transmission, to inform the EEC IV module
when the transmission is in neutral, and when
the kickdown is being operated.
The module provides outputs to control the
fuel pump, fuel injectors, idle speed, ignition
system and automatic transmission.
Additionally, on models with air conditioning,
the EEC IV module disengages the air
conditioning compressor clutch when starting
the engine, and when the engine is suddenly
accelerated. On models fitted with a catalytic
converter, the EEC IV module also controls
the carbon canister-purge solenoid valve.
Using the inputs from the various sensors,
the EEC IV module computes the optimum
ignition advance, and fuel injector pulse
duration to suit the prevailing engine
conditions. A “limited operation strategy” (LOS)means that the vehicle is still driveable, albeit at
reduced power and efficiency, in the event of a
failure in the module or one of its sensors.
1.6 litre and 1.8 litre (R6A type) CVH models
A development of the EEC IV system is
used to control both the ignition and fuel
injection systems. A fully electronic
Distributorless Ignition System (DIS) is fitted,
replacing the mechanical distribution of high
tension voltage (by a rotating distributor) with
“static” solid-state electronic components.
The system selects the most appropriate
ignition advance setting for the prevailing
engine operating conditions from a three-
dimensional map of values stored in the EEC
IV control module memory. The module
selects the appropriate advance value
according to information supplied on engine
load, speed, and operating temperature from
various sensors.
The EEC IV module receives information
from a crankshaft speed/position sensor
(similar to that described for the ESC Hybrid
system), except that on 1.6 litre engines, the
sensor is activated by a toothed disc on the
flywheel), a throttle position sensor, an engine
coolant temperature sensor, an air charge
temperature sensor, a manifold absolute
pressure (MAP) sensor, a vehicle speed
sensor (mounted on the gearbox), and an
exhaust gas oxygen sensor.
The module provides outputs to control the
fuel pump, fuel injector, throttle valve control
motor, pulse-air control solenoid, carbon
canister purge solenoid (where applicable),
and the ignition system.
Using the inputs from the various sensors,
the EEC IV module computes the optimum
ignition advance and fuel injector pulse dura-
tion to suit the prevailing engine conditions. A
“limited operation strategy” (LOS) means that
the vehicle will still be driveable, albeit at
reduced power and efficiency, in the event of
a failure in the module or one of its sensors.
Precautions
General
It is necessary to take extra care when
working on the electrical system to avoid
damage to semi-conductor devices (diodes
and transistors), and to avoid the risk of
personal injury. In addition to the precautions
given in the “Safety first!” Section at the
beginning of this manual, take note of the
following points when working on the system.
Always remove rings, watches, etc before
working on the electrical system. Even with
the battery disconnected, capacitive
discharge could occur if a component live
terminal is earthed through a metal object.
This could cause a shock or nasty burn.
Do not reverse the battery connections.
Components such as the alternator or any
other having semi-conductor circuitry could
be irreparably damaged.
If the engine is being started using jump
leads and a slave battery, connect the
batteries positive to positive and negative to
negative. This also applies when connecting a
battery charger.
5•4Engine electrical systems
Page 14 of 24

and/or a suppressor may be secured by one
of the coil securing bolts (see illustrations).
1.6 and 1.8 litre (R6A type) CVH
models
9Disconnect the battery negative lead.
10Remove the two securing screws, and
withdraw the plastic ignition module shroud.
11Disconnect the ignition coil wiring plug
and, where fitted, the suppressor wiring plug,
pulling on the plugs, not on the wiring (see
illustrations).
12Release the securing lugs, and disconnect
the HT leads from the coil, noting their
locations to aid refitting.
13Remove the four Torx screws, and
withdraw the coil from the cylinder block.
Refitting
14Refitting is a reversal of removal, but
ensure that all leads are securely connected.
SOHC models
1Disconnect the battery negative lead.
2Where applicable, unclip the screening can
from the top of the distributor and disconnect
the earth strap (see illustration).
3If necessary, identify each HT lead for
position, so that the leads can be refitted to
their correct cylinders, then disconnect the
leads from the spark plugs by pulling on the
connectors, not the leads. Similarly,
disconnect the HT lead from the coil. Where
applicable, slide the HT lead holder from the
clip on the camshaft cover (see illustration).
Lucas distributors
4Remove the two securing screws and lift off
the distributor cap.
5The rotor arm is a push-fit on the end of the
distributor shaft.
6Refitting is a reversal of removal, noting that
the rotor arm can only be fitted in one
position. Ensure that the HT leads are
correctly connected.
Bosch distributors
7Prise away the spring clips with a
screwdriver and lift off the distributor cap(see
illustration).On fuel injection models,
disconnect the crankcase ventilation hose
from the air inlet hose, then disconnect the air
inlet hose from the inlet manifold and the
airflow meter for improved access. 8Refitting is a reversal of removal, noting that
the rotor arm can only be fitted in one position.
Ensure that the HT leads are correctly
connected, and on fuel injection models
ensure that the air inlet hose clips are correctly
aligned (refer to illustration, Section 15,
Chapter 4, PartB).
Motorcraft distributors
9For improved access, disconnect the
crankcase ventilation hose from the air inlet
hose, then disconnect the air inlet hose from
the inlet manifold and the airflow meter for
improved access.
10Remove the two securing screws and lift
off the distributor cap (see illustration).
11Remove the two securing screws and
withdraw the rotor arm (disc) (see
illustration). Note that on some vehicles, the
rotor arm tip may be coated with silicone
grease to assist radio interference
suppression. Do not attempt to clean the
grease off if it is present. If radio interference
13Distributor cap and rotor arm
(OHC models) - removal and
refitting
5•14Engine electrical systems
12.8a Ignition coil viewed with heat shield
removed12.11a Disconnecting the coil wiring plug . . .
13.10 Removing a distributor cap securing
screw - Motorcraft distributor13.7 Securing distributor cap with spring
clip - Bosch distributor13.3 HT lead holder on camshaft cover
13.2 Unclipping the distributor screening
can - Motorcraft distributor
12.11b . . . and the suppressor wiring plug
12.8b Suppressor secured by one of the
coil securing bolts
Page 16 of 24

sprocket bolt. Note that there is no need to
remove the timing belt or the sprockets.
Note: During production the engine ignition
timing is accurately set using a microwave
process, and sealant is applied to the
distributor clamp bolt. Removal of the
distributor should be avoided except where
excessive bearing wear has occurred due to
high mileage or during major engine overhaul.
A timing light will be required to check the
ignition timing after refitting the distributor.
All models except early
“Economy”
Removal
1Disconnect the battery negative lead.
2If necessary, identify each HT lead for
position, so that the leads can be refitted to
their correct cylinders, then disconnect the
leads from the spark plugs by pulling on the
connectors, not the leads.
3Where applicable, unclip the screening can
from the top of the distributor and disconnect
the earth strap. On fuel injection models,
disconnect the crankcase ventilation hose
from the air inlet hose, then disconnect the air
inlet hose from the inlet manifold and the
airflow meter for improved access.4Prise away the spring clips with a
screwdriver, or remove the two securing
screws, as applicable, and lift off the
distributor cap.
5Disconnect the HT lead from the coil by
pulling on the connector, not the lead, then
slide the HT lead holder from the clip on the
camshaft cover, and withdraw the distributor
cap.
6Where applicable, disconnect the vacuum
pipe from the vacuum advance unit on the
side of the distributor (see illustration).
7Using a suitable socket or spanner on the
crankshaft pulley bolt, turn the crankshaft to
bring No 1 cylinder to the firing point. If the
distributor cap is secured by clips, make sure
that the clips stay clear of the distributormoving parts. No 1 cylinder is at the firing
point when:
a)The relevant timing marks are in
alignment.
b)The tip of the rotor arm is pointing to the
position occupied by the No 1 cylinder HT
lead terminal in the distributor cap. Note
that the position of No 1 HT lead terminal
is identified by a pip or a number “1”
c)On Lucas distributors, the cut-out in the
trigger vane is aligned with the sensor
(see illustration)
d)On Bosch distributors, the tip of the rotor
arm is aligned with the scribed line on the
distributor body (where applicable,
remove rotor arm and dust cover, then
refit rotor arm to check alignment with
scribed line) (see illustration)
e)On Motorcraft distributors, the tip of the
rotor arm is aligned with a notch in the
distributor body. Mark the relevant notch
(there may be several) for reference when
refitting. Also, the leading edge of one of
the trigger vane segments is aligned with
the rib on the sensor (remove the two
securing screws and lift off the rotor arm
to view the trigger vane and sensor) (see
illustration).
8Disconnect the distributor wiring plug,
where applicable depressing the locking
tab(s). Pull on the plug, not the wiring (see
illustration).
9Make alignment marks between the
distributor body and the cylinder block.
10Scrape the sealant from the distributor
clamp bolt, then unscrew and remove the bolt
and clamp (see illustration).
11Withdraw the distributor from the cylinder
block. As the distributor is removed, the rotor
arm will turn clockwise due to the skew gear
drive. Note the new position of the rotor arm
relative to the distributor body, if necessary
making an alignment mark (some distributors
already have an alignment mark).
12Check the distributor spindle for
excessive side-to-side movement. If evident,
the distributor must be renewed, as the only
spares available are the cap, rotor arm,
module (where applicable), and driveshaft
O-ring (see illustration).
15Distributor (OHC models) -
removal and refitting
5•16Engine electrical systems
14.9 Removing the rotor housing
15.7a Lucas distributor showing trigger
vane position No 1 cylinder at firing point
A Trigger vane cut
-outB Sensor
15.8 Disconnecting distributor wiring plug
- Bosch distributor15.7c Trigger vane segment leading edge
aligned with sensor rib - Motorcraft
distributor15.7b Rotor arm tip aligned with scribed
line on distributor body - Bosch distributor
15.6 Disconnecting vacuum pipe from
vacuum advance unit - Bosch distributor
Page 17 of 24

Refitting
13Commence refitting by checking that No 1
cylinder is still at the firing point. The relevant
timing marks should be aligned. If the engine
has been turned whilst the distributor has
been removed, check that No 1 cylinder is on
its firing stroke by removing the No 1 cylinder
spark plug and placing a finger over the plug
hole. Turn the crankshaft until compression
can be felt, which indicates that No 1 piston is
rising on its firing stroke. Continue turning the
crankshaft until the relevant timing marks are
in alignment.
14Turn the rotor arm to the position noted in
paragraph 11. If a new distributor is being
fitted, and no alignment marks are present,
transfer the marks from the old distributor to
the new distributor.
15Hold the distributor directly over the
aperture in the cylinder block with the
previously made marks on the distributor
body and cylinder block aligned, then lower
the distributor into position. Again, if a new
distributor is being fitted, transfer the
alignment mark from the old distributor body
to the new distributor body. As the skew gear
drive meshes, the rotor arm will turn
anti-clockwise.
16With the distributor fitted and the marks
on the distributor body and cylinder block
aligned, check that the rotor arm is positioned
as described in paragraph 7 -if not, withdraw
the distributor, re-position the driveshaft and
try again.
17Refit the clamp, then insert and tighten
the bolt. Do not fully tighten the bolt at this
stage.
18Refit the distributor wiring plug, and
where applicable reconnect the vacuum pipe,
and refit the dust cover and/or rotor arm.
19Refit the distributor cap, and reconnect
the HT leads to the spark plugs and coil.
Ensure that the leads are refitted to their
correct cylinders.
20Where applicable, refit the screening can
to the top of the distributor and reconnect the
earth strap. On fuel injection models,
reconnect the air inlet hose, ensuring that the
clips are correctly aligned (refer to illustration,
Section 15, Chapter 4, PartB).21Reconnect the battery negative lead.
22Check and if necessary adjust the ignition
timing.
Early “Economy” models
Removal
23Removal of the distributor fitted to these
models is a similar process to that described
above.
Refitting
24Turn the crankshaft to bring No 1 cylinder
to the firing point, with the 16º BTDC mark on
the crankshaft pulley aligned with the pointer
on the crankshaft front oil seal housing, as
described above.
25Fit the new distributor to the engine as
described above, then proceed as follows.
26Cut the original distributor wiring plug
from the wiring loom. Make the cut close to
the connector.
27Strip back 10 mm of insulation from each
of the wires on the wiring loom, and on the
adapter loom supplied with the new
distributor.
28Solder the adapter loom wires to the
corresponding identically coloured wires in
the main loom.
29Carefully insulate each individual soldered
joint using insulating tape, then apply tape to
cover the join between the looms.
30Fit a new distributor cap (and screening
can, where applicable), and connect the HT
leads.31Connect the adapter loom to the
distributor.
32Start the engine, and adjust the ignition
timing to the value given in the Specifications
at the beginning of this Chapter. Work as
described above whilst noting that the
vacuum pipe must be left connected.
Note: During production the ignition timing is
accurately set using a microwave process,
and sealant is applied to the distributor clamp
bolt. Because the electronic components
require no maintenance, checking the ignition
timing does not constitute part of the routine
maintenance schedule, and the procedure is
therefore only necessary after removal and
refitting of the distributor. A timing light will be
required for this procedure. For details of
ignition timing adjustment in order to operate
vehicles on unleaded petrol refer to the
appropriate Section of this Chapter.
All models except 2.0 litre DOHC
1Before checking the ignition timing, the
following conditions must be met:
a)The engine must be at normal operating
temperature
b)Where applicable, the vacuum pipe to the
distributor vacuum unit or electronic
module (as applicable) must be
disconnected from the vacuum unit or
electronic module and plugged
c)The idle speed must be below 900 rpm
(isolate “idle speed adjustment” wire if
necessary)
d)Any earthed “octane adjustment” wires
must be temporarily isolated
2Wipe clean the crankshaft pulley timing
marks and the pointer on the crankshaft front
oil seal housing. Note that two alternative
types of pulley may be fitted (see
illustration).The desired timing values are
given in the Specifications. If necessary, use
white paint or chalk to highlight the relevant
timing mark(s) (see illustration).
3Connect a stroboscope timing light to the
No 1 cylinder HT lead, following the
manufacturer’s instructions.
4With the engine idling at normal operating
temperature, point the timing light at the
marks on the crankshaft pulley, and check
that the appropriate timing mark appears
stationary in line with the timing cover pointer.
Take care not to get the timing light leads,
clothing etc tangled in the cooling fan blades
or other moving parts of the engine.
5If adjustment is necessary, stop the engine,
slacken the distributor clamp bolt, and turn
the distributor body slightly. Turn the
distributor body clockwise to retard the
ignition timing (move the timing closer to TDC)
and anti-clockwise to advance the timing.
16Ignition timing (OHC models)
- adjustment
Engine electrical systems 5•17
5
15.12 Removing distributor driveshaft O-
ring - Motorcraft distributor15.10 Unscrewing distributor clamp bolt -
Bosch distributor
16.2a Highlighted timing marks - SOHC
engine with cast crankshaft pulley
Page 18 of 24

Note that the required distributor body
movement will be half of the required
crankshaft movement (ie an adjustment of 5º
in ignition timing will require the distributor
body to be turned 2º. Tighten the clamp bolt
and re-check the timing.
6On models with inductive discharge ignition
systems, the mechanical and vacuum
advance mechanisms can be checked as
follows. On all other models, proceed to
paragraph 10.
7With the engine idling, timing light
connected, and vacuum pipe disconnected as
described in the preceding paragraphs,
increase the engine speed to approximately
2000 rpm (if desired, connect a tachometer to
the engine in accordance with the
manufacturer”s instructions). Note the
approximate distance which the relevant pulley
mark moves out of alignment with the pointer.
8Reconnect the vacuum pipe to the
distributor or electronic module, as
applicable, and repeat the procedure given in
the previous paragraph, when for the same
increase in engine speed, the alignment
differential between the pulley mark and
pointer should be greater than previously
observed.
9If the pulley mark does not appear to move
during the first part of the check, a fault in the
distributor mechanical advance mechanism is
indicated. No increased movement of the
mark during the second part of the check
indicates a punctured diaphragm in the
distributor vacuum unit, or a leak in the
vacuum line.
10On completion of the adjustments and
checks, stop the engine and disconnect the
timing light. Where applicable, reconnect the
vacuum pipe, if not already done, and
reconnect any “octane adjustment” and “idle
speed adjustment” wires. Make a final check
to ensure that the distributor clamp bolt is
tight.
11Finally, the idle speed and mixture should
be checked and adjusted.2.0 litre DOHC carburettor model
12The ignition timing is controlled by the
ESC II module, and no adjustment is possible.
2.0 litre DOHC fuel injection
model
13The ignition timing is controlled by the
EEC IV module, and no adjustment is
possible.
Note: Refer to the Specifications Section at
the beginning of this Chapter for ignition
timing values for use with unleaded petrol.
1To run an engine on unleaded petrol,
certain criteria must be met, and it may be
helpful to first describe the various terms used
for the different types of petrol:
Normal leaded petrol (4-star, 97 RON):
Petrol which has a low amount of lead added
during manufacture (0.15 g/litre), in addition to
the natural lead found in crude oil.
Unleaded petrol (Premium, 95 RON):
Has no lead added during manufacture, but
still has the natural lead content of crude oil.
Lead free petrol: Contains no lead. It has
no lead added during manufacture, and the
natural lead content is refined out. This
type of petrol is not currently available for
general use in the UK and should not be
confused with unleaded petrol.
2To run an engine continuously on unleaded
petrol, suitable hardened valve seat inserts
must be fitted to the cylinder head.
3The OHC engines fitted to the Sierra/P100
range which have suitable valve seat inserts
fitted at manufacture can be identified by
letters stamped on the cylinder head next to
No 4 spark plug as follows:
1.6 litre enginesM, MM, N, or NN
1.6 litre enginesS or SS
2.0 litre enginesL, P, PP, R, or RR4All CVH engines have suitable valve seat
inserts fitted.
5Vehicles which have no identification letter
stamped on the cylinder head, and are not
fitted with suitable valve seat inserts, may still
be run on unleaded petrol (although
continuous use is not recommended),
provided that every fourth tank filling is of
normal leaded petrol, ie: three tanks of
unleaded petrol followed by one tank of
normal leaded petrol.
6When running an OHC engine on unleaded
petrol (Premium, 95 RON), the ignition timing
must be retarded as described in the
following sub-Sections. There is no
requirement for ignition timing adjustment
when running CVH engines on unleaded
petrol.
Inductive discharge ignition
system and ESC system
7On vehicles fitted with an inductive
discharge ignition system, or the ESC system,
the ignition timing should be retarded as
specified.
ESC II and EEC IV systems
8On vehicles fitted with the ESC II or EEC IV
systems, there is a facility for retarding the
ignition timing without physically disturbing
the distributor.
9Adjustment is made by earthing one or two
wires (“octane adjustment” wires) which
terminate in a wiring plug next to the ignition
coil. Ideally a service adjustment lead,
available from a Ford dealer should be used
(see illustration). One end of the lead plugs
into the “octane adjustment” wiring plug, and
the other end should be earthed by fixing to
one of the ignition coil securing screws.
10Cut and insulate the wires in the service
lead which are not to be earthed.
17Ignition timing -adjustmentfor
usewithunleadedpetrol
5•18Engine electrical systems
17.9 Service adjustment lead and plug -
ESC II and EEC IV systems
A Red, blue and yellow wires
B Plug
C Wire cutting point
16.2b Crankshaft pulley timing marks - SOHC engine
A Cast pulleyB Pressed steel pulley
Page 20 of 24

EEC IV modules
Ignition module
Models up to 1987
Note: When refitting, the rear face of the
module must be coated with heat sink
compound. Refer to a Ford dealer for advice if
necessary.
12The module is mounted on the distributor
body.
13Disconnect the distributor wiring plug by
depressing the locking tabs. Pull on the plug,
not the wiring.
14Remove the two securing screws from the
module, then slide the module downwards
and withdraw it (see illustration).
15Refitting is a reversal of removal, but the
rear face of the module must be coated with
heat sink compound. Do not force the module
into position, as damage to the electrical
contacts may result.
Models from 1987
16The module is mounted on the left-hand
side of the engine compartment (see
illustration).
17Disconnect the module wiring plug by
depressing the locking tabs. Pull on the plug,
not the wiring.
18Remove the two securing screws and
withdraw the module from the engine
compartment.
19Refitting is a reversal of removal, but
ensure that the underside of the module and
the corresponding area of the body panel are
clean.
1.6 and 1.8 litre (R6A type) CVH models
20The ignition module is located at the front
right-hand side of the engine compartment. 21Disconnect the battery negative lead.
22Release the securing lug, and pull the
wiring plug from the module. Pull on the plug,
not on the wiring (see illustration).
23Remove the two securing screws, and
withdraw the module from the body panel.
24Refitting is a reversal of removal.
2.0 litre DOHC fuel injection models
25The ignition module is located on the left-
hand side of the engine compartment,
beneath the coil (see illustration).
26Disconnect the battery negative lead.
27Remove the two securing screws, and
withdraw the coil/ignition module heat shield.
28Release the locking lug and disconnect
the ignition module wiring plug. Pull on the
plug, not on the wiring.
29Remove the two securing screws, and
withdraw the module from the body panel.
30Refitting is a reversal of removal, ensuring
that the underside of the module and the
corresponding area of the body panel are clean.
Engine management module
All models except 1.6 and 1.8 litre CVH
(R6A type) and 2.0 litre DOHC fuel injection
31The module is located inside the
passenger compartment behind the
passenger side facia.
32Unclip the trim panel from below the
glovebox on models up to 1987, or from
above the glovebox on models from 1987.
33Unclip the module retainer and withdraw
the module.
34The wiring plug is secured by a screw
which is integral with the plug. Disconnect the
wiring plug and remove the module.35Refitting is a reversal of removal, noting
that the wiring plug will only fit in one position.
1.6 and 1.8 litre (R6A type) CVH models
36The module is located in the passenger
compartment, behind the glovebox.
37Disconnect the battery negative lead.
38Open the glovebox, and carefully pull it
from its retaining clips.
39Unclip and withdraw the module from its
retaining bracket (see illustration).
40The wiring plug is secured by a screw
which is integral with the plug. Disconnect the
wiring plug, and withdraw the module.
41Refitting is a reversal of removal, noting
that the wiring plug will only fit in one position.
2.0 litre DOHC fuel injection models
42For models up to 1990 refer to the first 5
paragraphs of this sub Section.
43For models from 1990 refer to the
procedure given for 1.6 and 1.8 litre CVH (R6A
type) engines.
Note: Procedures for removal and refitting of
the ignition system components and
electronic module are given elsewhere in the
relevant Sections of this Chapter.
1Disconnect the battery negative lead.
Engine coolant temperature
sensor
All models except 2.0 litre DOHC
2The sensor is located in the underside of
the inlet manifold.
19ESC II system components -
removal and refitting
5•20Engine electrical systems
18.14 EEC IV ignition module securing
screws (arrowed) - models up to 198718.22 Disconnecting the ignition module
wiring plug
19.4 Disconnect engine temperature
sensor wiring plug - ESC II system18.39 Engine management module
withdrawn from its mounting bracket18.25 Ignition module location (arrowed)
18.16 EEC IV ignition module - models
from 1987
Page 23 of 24

25Remove the two securing screws and
detach the throttle damper and bracket
assembly from the carburettor (see
illustration).
26Commence refitting by securing the
throttle damper and bracket assembly to the
carburettor with the two screws. Ensure that
the throttle lever is correctly positioned in the
slot in the throttle damper actuating arm.
27Reconnect the vacuum pipe to the throttle
damper.
28Reconnect the air cleaner vacuum hose to
the inlet manifold, and reconnect the air
change temperature sensor wiring plug, then
place the air cleaner to one side to allow
access to the throttle damper.
29Reconnect the battery negative lead.
30Connect a tachometer to the engine in
accordance with the manufacturer’s
instructions.
31Start the engine, then check and if
necessary adjust the idle speed and mixture.
32Earth the “service adjustment” lead,
located in the battery negative wiring loom
(see illustration), for a minimum of 10
seconds. The throttle damper actuating arm
should move to the fully retracted position,
raising the engine speed.
33The engine speed should stabilise at 1700
±100 rpm. If adjustment is necessary, turn
the adjusting screw on the end of the throttle
damper actuating arm to give the correct
speed. Turn the screw clockwise to increase
the engine speed, or anti-clockwise to reduce
the engine speed.34On completion of adjustment, stop the
engine and disconnect the tachometer.
35Where necessary, ensure that any
tamperproof seals are refitted, then refit the
air cleaner, ensuring that the vacuum hose is
securely connected. Isolate the “service
adjustment” lead.
36Start the engine and check that normal
idle speed is resumed, then stop the engine.
Note:Procedures for removal and refitting of
the ignition system components and
electronic module are given elsewhere in the
relevant Sections of this Chapter.
Engine coolant temperature
sensor
2.0 litre SOHC fuel injection models
1For details of engine coolant temperature
sensor removal and refitting, refer to the
Section appertaining to the ESC II system.
1.6 and 1.8 litre (R6A type) CVH models
2The sensor is located in the side of the inlet
manifold.
3Disconnect the battery negative lead.
4Partially drain the cooling system.
5Disconnect the sensor wiring plug by
pulling on the plug, not the wiring (see
illustration).
6Unscrew the sensor from the inlet manifold
and remove it.
7Refitting is a reversal of removal. Refill the
cooling system.
2.0 litre DOHC fuel injection models
8The sensor is located in the side of the inlet
manifold, behind the throttle body. The
removal and refitting procedure is as
described for the 1.6 and 1.8 litre (R6A type)
CVH models above.
Crankshaft speed/position sensor
1.6 and 1.8 litre (R6A type) CVH
models
1.6 litre
9The sensor is located at the left-hand rear
of the cylinder block, above the starter motor
(see illustration).10Disconnect the battery negative lead.
11Remove the securing screw, and
withdraw the sensor shroud.
12Disconnect the sensor wiring plug.
13Remove the Torx securing screw, and
withdraw the sensor.
14Refitting is a reversal of removal.
1.8 litre
15Proceed as described for the ESC Hybrid
module. If a new sensor (not the original unit)
is being fitted, position it in the mounting
bracket so that it is in actual contact with one
of the teeth of the toothed wheel on the
crankshaft. Hold the sensor in this position,
and tighten the clamping screw. New sensors
have projections on their base, which will
wear away when the engine is cranking, and
automatically set the specified clearance.
2.0 litre DOHC fuel injection models
16This procedure is as described for the 2.0
litre DOHC carburettor models (ESC II
module).
Air charge temperature sensor
1.6 and 1.8 litre (R6A type) CVH
models
17The sensor is located in the side of the
CFI unit on 1.6 litre engines (see illustration),
and on the inlet manifold on 1.8 litre engines.
18Disconnect the battery negative lead.
19Disconnect the sensor wiring plug by
pulling on the plug, not the wiring.
20Unscrew the sensor from its location, and
remove it.
21Refitting is a reversal of removal, but coat
the threads of the sensor with suitable sealant
before fitting.
2.0 litre DOHC fuel injection models
22The sensor is located in the upper section
of the inlet manifold.
23Disconnect the battery negative lead.
24Disconnect the sensor wiring plug by
pulling on the plug, not the wiring (see
illustration).
25Unscrew the sensor from the inlet
manifold, and remove it.
26Refitting is a reversal of removal, noting
the torque setting for the sensor.
21EEC IV system components -
removaland refitting
Engine electrical systems 5•23
5
21.9 Crankshaft speed/position sensor
(arrowed) viewed from front of engine with
shroud removed21.17 Air charge temperature sensor
location on 1.6 litre engines (arrowed)
21.5 Disconnecting the engine coolant
temperature sensor wiring plug20.32 Service adjustment lead location
(arrowed) - ESC Hybrid system