relay OPEL FRONTERA 1998 Workshop Manual

6E–342
ENGINE DRIVEABILITY AND EMISSIONS
PCM to calculate true sequential multiport fuel injection
(SFI). Loss of this signal will set a DTC P0341. If the CMP
signal is lost while the engine is running, the fuel injection
system will shift to a calculated sequential fuel injection
based on the last fuel injection pulse, and the engine will
continue to run. The engine can be restarted and will run
in the calculated sequential mode as long as the fault is
present, with a 1-in-6 chance of being correct.
Clear Flood Mode
Clear a flooded engine by pushing the accelerator pedal
down all the way. The PCM then de-energizes the fuel
injectors. The PCM holds the fuel injectors de-energized
as long as the throttle remains above 80% and the engine
speed is below 800 RPM. If the throttle position becomes
less than 80%, the PCM again begins to pulse the
injectors “ON” and “OFF,” allowing fuel into the cylinders.
Deceleration Mode
The PCM reduces the amount of fuel injected when it
detects a decrease in the throttle position and the air flow.
When deceleration is very fast, the PCM may cut off fuel
completely for short periods.
Engine Speed/Vehicle Speed/Fuel Disable
Mode
The PCM monitors engine speed. It turns off the fuel
injectors when the engine speed increase above 6400
RPM. The fuel injectors are turned back on when engine
speed decreases below 6150 RPM.
Fuel Cutoff Mode
No fuel is delivered by the fuel injectors when the ignition
is “OFF.” This prevents engine run-on. In addition, the
PCM suspends fuel delivery if no reference pulses are
detected (engine not running) to prevent engine flooding.
Fuel Injector
The sequential multiport fuel injection (SFI) fuel injector is
a solenoid-operated device controlled by the PCM. The
PCM energizes the solenoid, which opens a valve to allow
fuel delivery.
The fuel is injected under pressure in a conical spray
pattern at the opening of the intake valve. Excess fuel not
used by the injectors passes through the fuel pressure
regulator before being returned to the fuel tank.
A fuel injector which is stuck partly open will cause a loss
of fuel pressure after engine shut down, causing long
crank times.
0003
Fuel Metering System Components
The fuel metering system is made up of the following
parts:
The fuel injectors.
The throttle body.
The fuel rail.
The fuel pressure regulator.
The PCM.
The crankshaft position (CKP) sensor.
The camshaft position (CMP) sensor.
The idle air control (IAC) valve.
The fuel pump.
The fuel pump relay.
Basic System Operation
The fuel metering system starts with the fuel in the fuel
tank. An electric fuel pump, located in the fuel tank,
pumps fuel to the fuel rail through an in-line fuel filter. The
pump is designed to provide fuel at a pressure above the
pressure needed by the injectors. A fuel pressure
regulator in the fuel rail keeps fuel available to the fuel
injectors at a constant pressure. A return line delivers
unused fuel back to the fuel tank. Refer to
Section 6C f o r
further information on the fuel tank, line filter, and fuel
pipes.
Fuel Metering System Purpose
The basic function of the air/fuel metering system is to
control the air/fuel delivery to the engine. Fuel is delivered
to the engine by individual fuel injectors mounted in the
intake manifold near each intake valve.
The main control sensor is the heated oxygen sensor
(HO2S) located in the exhaust system. The HO2S tells
the PCM how much oxygen is in the exhaust gas. The
PCM changes the air/fuel ratio to the engine by controlling
the amount of time that fuel injector is “ON.” The best
mixture to minimize exhaust emissions is 14.7 parts of air
to 1 part of gasoline by weight, which allows the catalytic
converter to operate most efficiently. Because of the

6E–343 ENGINE DRIVEABILITY AND EMISSIONS
constant measuring and adjusting of the air/fuel ratio, the
fuel injection system is called a “closed loop” system.
The PCM monitors signals from several sensors in order
to determine the fuel needs of the engine. Fuel is
delivered under one of several conditions called “modes.”
All modes are controlled by the PCM.
Fuel Pressure Regulator
The fuel pressure regulator is a diaphragm-operated
relief valve mounted on the fuel rail with fuel pump
pressure on one side and manifold pressure on the other
side. The fuel pressure regulator maintains the fuel
pressure available to the injector at three times
barometric pressure adjusted for engine load. It may be
serviced separate.
If the pressure is too low, poor performance and a DTC
P0131, DTC P0151,DTC P0171 or DTC P1171 will be the
result. If the pressure is too high, excessive odor and/or a
DTC P0132, DTC P0152,DTC P0172 or DTC P0175 will
be the result. Refer to
Fuel System Diagnosis for
information on diagnosing fuel pressure conditions.
0011
Fuel Pump Electrical Circuit
When the key is first turned “ON,” the PCM energizes the
fuel pump relay for two seconds to build up the fuel
pressure quickly. If the engine is not started within two
seconds, the PCM shuts the fuel pump off and waits until
the engine is cranked. When the engine is cranked and
the 58 X crankshaft position signal has been detected by
the PCM, the PCM supplies 12 volts to the fuel pump relay
to energize the electric in-tank fuel pump.
An inoperative fuel pump will cause a “no-start” condition.
A fuel pump which does not provide enough pressure will
result in poor performance.
Fuel Rail
The fuel rail is mounted to the top of the engine and
distributes fuel to the individual injectors. Fuel is
delivered to the fuel inlet tube of the fuel rail by the fuel
lines. The fuel goes through the fuel rail to the fuel
pressure regulator. The fuel pressure regulator maintainsa constant fuel pressure at the injectors. Remaining fuel
is then returned to the fuel tank.
055RW009
Idle Air Control (IAC) Valve
The purpose of the idle air control (IAC) valve is to control
engine idle speed, while preventing stalls due to changes
in engine load. The IAC valve, mounted in the throttle
body, controls bypass air around the throttle plate. By
moving the conical valve (pintle) in (to decrease air flow)
or out (to increase air flow), a controlled amount of air can
move around the throttle plate. If the RPM is too low, the
PCM will retract the IAC pintle, resulting in more air
moving past the throttle plate to increase the RPM. If the
RPM is too high, the PCM will extend the IAC pintle,
allowing less air to move past the throttle plate,
decreasing the RPM.
The IAC pintle valve moves in small steps called counts.
During idle, the proper position of the IAC pintle is
calculated by the PCM based on battery voltage, coolant
temperature, engine load, and engine RPM. If the RPM
drops below a specified value, and the throttle plate is
closed, the PCM senses a near-stall condition. The PCM
will then calculate a new IAC pintle valve position to
prevent stalls.
If the IAC valve is disconnected and reconnected with the
engine running, the idle RPM will be wrong. In this case,
the IAC must be reset. The IAC resets when the key is
cycled “ON” then “OFF.” When servicing the IAC, it
should only be disconnected or connected with the
ignition “OFF.”
The position of the IAC pintle valve affects engine start-up
and the idle characteristics of the vehicle. If the IAC pintle
is fully open, too much air will be allowed into the manifold.
This results in high idle speed, along with possible hard
starting and a lean air/fuel ratio. DTC P0507 or DTC
P1509 may set. If the IAC pintle is stuck closed, too little
air will be allowed in the manifold. This results in a low idle
speed, along with possible hard starting and a rich air/fuel
ratio. DTC P0506 or DTC P1508 may set. If the IAC
pintle is stuck part-way open, the idle may be high or low
and will not respond to changes in the engine load.

6E–344
ENGINE DRIVEABILITY AND EMISSIONS
0006
Run Mode
The run mode has the following two conditions:
Open loop
Closed loop
When the engine is first started the system is in “open
loop” operation. In “open loop,” the PCM ignores the
signal from the heated oxygen sensor (HO2S). It
calculates the air/fuel ratio based on inputs from the TP,
ECT, and MAF sensors.
The system remains in “open loop” until the following
conditions are met:
The HO2S has a varying voltage output showing that
it is hot enough to operate properly (this depends on
temperature).
The ECT has reached a specified temperature.
A specific amount of time has elapsed since starting
the engine.
Engine speed has been greater than a specified RPM
since start-up.
The specific values for the above conditions vary with
different engines and are stored in the programmable
read only memory (PROM). When these conditions are
met, the system enters “closed loop” operation. In
“closed loop,” the PCM calculates the air/fuel ratio
(injector on-time) based on the signal from the HO2S.
This allows the air/fuel ratio to stay very close to 14.7:1.
Starting Mode
When the ignition is first turned “ON,” the PCM energizes
the fuel pump relay for two seconds to allow the fuel pump
to build up pressure. The PCM then checks the engine
coolant temperature (ECT) sensor and the throttle
position (TP) sensor to determine the proper air/fuel ratio
for starting.
The PCM controls the amount of fuel delivered in the
starting mode by adjusting how long the fuel injectors are
energized by pulsing the injectors for very short times.
Throttle Body Unit
The throttle body has a throttle plate to control the amount
of air delivered to the engine. The TP sensor and IAC
valve are also mounted on the throttle body. Vacuum
ports located behind the throttle plate provide the vacuum
signals needed by various components.
Engine coolant is directed through a coolant cavity in the
throttle body to warm the throttle valve and to prevent
icing.
0019
General Description (Electronic
Ignition System)
Camshaft Position (CMP) Sensor
As the camshaft sprocket turns, a magnet in the sprocket
activates the Hall-effect switch in the CMP sensor. When
the Hall-effect switch is activated, it grounds the signal
line to the PCM, pulling the camshaft position sensor
signal circuit’s applied voltage low. This is a CMP signal.
The CMP signals is created as piston #1 is approximately
25
after top dead counter on the power stroke. If the
correct CMP signal is not received by the PCM, DTC
P0341 will be set.

6E–349 ENGINE DRIVEABILITY AND EMISSIONS
Damage during re-gapping can happen if the gapping
tool is pushed against the center electrode or the
insulator around it, causing the insulator to crack.
When re-gapping a spark plug, make the adjustment
by bending only the ground side terminal, keeping the
tool clear of other parts.
”Heat shock” breakage in the lower insulator tip
generally occurs during several engine operating
conditions (high speeds or heavy loading) and may be
caused by over-advanced timing or low grade fuels.
Heat shock refers to a rapid increase in the tip
temperature that causes the insulator material to
crack.
Spark plugs with less than the recommended amount of
service can sometimes be cleaned and re-gapped , then
returned to service. However, if there is any doubt about
the serviceability of a spark plug, replace it. Spark plugs
with cracked or broken insulators should always be
replaced.
A/C Clutch Diagnosis
A/C Clutch Circuit Operation
A 12-volt signal is supplied to the A/C request input of the
PCM when the A/C is selected through the A/C control
switch.
The A/C compressor clutch relay is controlled through the
PCM. This allows the PCM to modify the idle air control
position prior to the A/C clutch engagement for better idle
quality. If the engine operating conditions are within their
specified calibrated acceptable ranges, the PCM will
enable the A/C compressor relay. This is done by
providing a ground path for the A/C relay coil within the
PCM. When the A/C compressor relay is enabled,
battery voltage is supplied to the compressor clutch coil.
The PCM will enable the A/C compressor clutch
whenever the engine is running and the A/C has been
requested. The PCM will not enable the A/C compressor
clutch if any of the following conditions are met:
The throttle is greater than 90%.
The engine speed is greater than 6315 RPM.
The ECT is greater than 119C (246F).
The IAT is less than 5C (41F).
The throttle is more than 80% open.
A/C Clutch Circuit Purpose
The A/C compressor operation is controlled by the
powertrain control module (PCM) for the following
reasons:
It improvises idle quality during compressor clutch
engagement.
It improvises wide open throttle (WOT) performance.
It provides A/C compressor protection from operation
with incorrect refrigerant pressures.
The A/C electrical system consists of the following
components:
The A/C control head.
The A/C refrigerant pressure switches.
The A/C compressor clutch.
The A/C compressor clutch relay.
The PCM.
A/C Request Signal
This signal tells the PCM when the A/C mode is selected
at the A/C control head. The PCM uses this to adjust the
idle speed before turning on the A/C clutch. The A/C
compressor will be inoperative if this signal is not
available to the PCM.
Refer to
A/C Clutch Circuit Diagnosis for A/C wiring
diagrams and diagnosis for A/C electrical system.
General Description (Exhaust Gas
Recirculation (EGR) System)
EGR Purpose
The exhaust gas recirculation (EGR) system is use to
reduce emission levels of oxides of nitrogen (NOx). NOx
emission levels are caused by a high combustion
temperature. The EGR system lowers the NOx emission
levels by decreasing the combustion temperature.
057RW002
Linear EGR Valve
The main element of the system is the linear EGR valve.
The EGR valve feeds small amounts of exhaust gas back
into the combustion chamber. The fuel/air mixture will be
diluted and combustion temperatures reduced.
Linear EGR Control
The PCM monitors the EGR actual positron and adjusts
the pintle position accordingly. The uses information from
the following sensors to control the pintle position:
Engine coolant temperature (ECT) sensor.
Throttle position (TP) sensor.
Mass air flow (MAF) sensor.
Linear EGR Valve Operation and Results
of Incorrect Operation
The linear EGR valve is designed to accurately supply
EGR to the engine independent of intake manifold
vacuum. The valve controls EGR flow from the exhaust

6G–7 ENGINE LUBRICATION
Oil Pan and Crankcase
Removal
1. Disconnect battery ground cable.
2. Drain engine oil.
3. Lift vehicle by supporting the frame.
4. Remove front wheels.
5. Remove oil level dipstick from level gauge tube.
6. Remove stone guard.
7. Remove radiator under fan shroud.
8. Remove suspension cross member fixing bolts, 2 pcs
each per side and remove suspension cross member.
9. Remove pitman arm and relay lever assembly, using
the 5–8840–2005–0 remover, remove pitman arm
from the steering unit and remove four fixing bolts for
relay lever assembly.
10. Remove axle housing assembly four fixing bolts from
housing isolator side and mounting bolts from wheel
side. At this time support the axle with a garage jack
and remove axle housing assembly.
11. Remove oil pan fixing bolts.
12. Remove oil pan, using 5–8840–2153–0 sealer cutter,
remove oil pan.
013RS003
13. Remove crankcase fixing bolts.
14. Remove crankcase, using 5–8840–2153–0 sealer
cutter, remove crankcase.
NOTE: Do not deform or damage the flange of oil pan and
crankcase.
Replace the oil pan and/or crankcase if deformed or dam-
aged.
013RS003
Installation
1. Install crankcase.
1. Remove residual sealant, lubricant and moisture
from mounting surface, then dry thoroughly.
2. Properly apply a 4.5 mm (0.7 in) wide bead of
sealant (TB-1207C or equivalent) to mounting
surface of crankcase.
Sealant beat must be continuous.
The crankcase must be installed within 5
minutes after sealant application before the
sealant hardens.
013RW010

6G–8
ENGINE LUBRICATION
3. Install crankcase, tighten crankcase fixing bolts
to the specified torque.
Torque : 10 Nꞏm (1.0 Kgꞏm/89 lb in)
013RW004
2. Install oil pan
1. Remove residual sealant, lubricant and moisture
from mounting surface, then dry thoroughly.
2. Properly apply a 4.5 mm (07 in) wide bead of
sealant (TB-1207C or equivalent) to mounting
surface of oil pan.
Sealant beat must be continuous.
The crankcase must be installed within 5
minutes after sealant application befor the
sealant hardens.
013RW003
3. Install oil pan, tighten oil pan fixing bolts to the
specified torque.
Torque : 25 Nꞏm (2.5 Kgꞏm/18 lb ft)3. Install axle housing assembly and tighten fixing bolts
to the specified torque.
Axle case bolts
Torque : 82 Nꞏm (8.4 Kgꞏm/60 lb ft)
Mounting bolts
Torque : 152 Nꞏm (15.5 Kgꞏm/112 lb ft)
013RW005
4. Install relay lever assembly and tighten fixing bolts.
Torque: 44 Nꞏm (4.5 Kgꞏm/32 lb ft)
5. Engage teeth of pitman arm and steering unit, and
tighten nut to the specified torque.
Torque : 216 Nꞏm (22.0 Kgꞏm/159 lb ft)
013RW006
Legend
(1) Pitman Arm
(2) Relay Lever

ST
ON
OFF
ON
OFF
ON
OFF
ON
OFF
18Km/h
9km/h
ON
OFF
ON
OFF
ON
OFF Starter SW
Starter SW is turned to
“ST” before indicator light
goes out.Starter SW is turned to
“ST” after indicator light
goes out.Starter SW
is left “ON”
Indicator timer
After glow timer
Charge relay
Indicator light
Relay 1
Relay 2Above
Vehicle speed below
t i t i t i
t a t a
t d t d t d t d
Glow plug
temperature
0t 0t 0t
: Indicator light “ON” time
: Rapid after glow (Delay timer) time
: After glow time
ti
td
ta
(For broken lines,
water temperature
is 70
C or above)

ENGINE MECHANICAL 6A – 13
VALVE CLEARANCE ADJUSTMENT
1. Install 2.80 mm valve adjuster (shim) first when
reassembling the engine.
Thickness mark faces down.
2. Measure the valve clearance after installing cam
carrier assy with camshafts.
3. Change the adjuster using a special tool when the
clearance is out of tolerance.
Valve Clearance Adjusting Tool: 5-8840-2590-0
VALVE CLEARANCE (When cold condition)
Inlet 0.15 ± 0.05 mm
Exh 0.25 ± 0.05 mm
COMPRESSION PRESSURE
MEASUREMENT
1. Start the engine and allow it to idle until the coolant
temperature reaches 70 – 80°C (158 – 176°F).
2. Remove the following parts.
Glow plugs
Fuel cut solenoid connector
QOS (Quick-On Start System) fuse in the fuse
box.
3. Set the adapter and compression gauge to the No.
1 cylinder glow plug hole.
Compression Gauge
(with Adapter): 5-8840-2008-0
4. Turn the engine over with the starter motor and take
the compression gauge reading.
Compression Pressure at 200 rpm
Standard: 3038 kPa (31 kg/cm
2/441 psi)
Limit: 2157 kPa (22 kg/cm
2/313 psi)
5. Repeat the procedure (Steps 3 and 4) for the
remaining cylinders.
QUICK-ON START 4 SYSTEM
Quick-On Start System Inspection Procedure
1. Disconnect the ECT-sensor connection around the
thermostat outlet pipe.
2. Turn the starter switch to the “ON” position.
If the Quick-On Start 4 System is operating
properly, the glow relay will make a clicking sound
within seven seconds after the starter switch is
turned on.
3. Measure the glow plug terminal voltage with a
circuit tester immediately after turning the starter
switch to the “ON” position.
Glow Plug Terminal Voltage: 8 – 9V
NOTE: Electrical power to the quick-on start system will
be cut after the starter has remained in the “ON”
position for twenty seconds.
Turn the starter switch to the “OFF” position and back
to the “ON” position.
This will reset the Quick-On Start 4 System.
014RW150

ENGINE ELECTRICAL 6D – 5
STARTING SYTEM
GENERAL DESCRIPTION
STARTING CIRCUIT
The cranking system consists of a battery, starter, starter switch, starter relay, etc. and these main
components are connected as shown in the illustration.
“S”
“B”
“M”
5
4
32 IG1ST
B2
B1
1
76
P
NN
Legend
(1) Inhibitor Switch
(2) Starter Switch
(3) Battery(4) Magnetic Switch
(5) Pinion Clutch
(6) Starter Motor
(7) Starter Relay
065RW039
STARTER
The starting system employs a magnetic type reduction
starter in which the motor shaft is also used as a pinion
shaft. When the starter switch is turned on, the contacts
of the magnetic switch are closed, and the armature
rotates. At the same time, the plunger is activated, and
the pinion is pushed forward by the shift lever to mesh
with ring gear.Then, the ring gear runs to start the engine. When the
engine starts and the starter switch is turned off, the
plunger returns, the pinion is disengaged from the ring
gear, and the armature stops rotation. When the engine
speed is higher than the pinion, the pinion idles, so that
the armature is not driven.

6D – 6 ENGINE ELECTRICAL
RELATION BETWEEN STARTER SWITCH AND STARTER
M
Key
PositionB1 B2 ACCIG1 IG2 ST
LOCKKey
Removed
Inserted OFF
ACC
ON
START
BSBattery
5 +-
2
16
3
4
Legend
(1) Starter Switch
(2) To Generator
(3) To QOS4 Control(4) Starter Relay
(5) Magnetic Switch
(6) Battery
065RW036