ECO mode FIAT UNO 1983 Service Manual PDF
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Page 178 of 303

bearing caps with a soft non-fluffy rag, then fit
the lower halves of the bearing shells to their
seats. Again, note that the centre (No. 3)
bearing shell is plain, whereas all the other
shells have oil grooves (photo).
9Lubricate the crankshaft journals and the
upper and lower main bearing shells with
clean engine oil (photo).
10Carefully lower the crankshaft into the
crankcase (photo). If necessary, seat the
crankshaft using light taps with a
rubber-faced hammer on the crankshaft
balance webs.
11Lubricate the crankshaft main bearing
journals again, the fit the No. 1 bearing cap.
Fit the two securing bolts, and tighten them as
far as possible by hand.
12Fit the No. 5 bearing cap, and as before
tighten the bolts as far as possible by hand.
13Fit the centre and then the intermediate
bearing caps, and again tighten the bolts as
far as possible by hand.
14Check that the markings on the bearing
caps are correctly orientated as noted during
dismantling - ie the identification grooves
should face towards the timing side of the
engine, then working from the centre cap
outwards in a progressive sequence, finally
tighten the bolts to the specified torque
(photo).
15Check that the crankshaft rotates freely.
Some stiffness is to be expected with new
components, but there should be no tight
spots or binding.16Check that crankshaft endfloat is within
the specified limits, as described in paragraph
70 of Part C in this Section.
17Examine the condition of the front and
rear crankshaft oil seals and renew if
necessary with reference to Part B of this
Section. It is advisable to renew the oil seals
as a matter of course unless they are in
perfect condition.
18Lubricate the oil seal lips with clean
engine oil, then carefully fit the front and rear
oil seal housings using new gaskets.
Pistons and connecting rods -
refitting
19Refer to Part B of this Section.
Oil pump - refitting
20Refer to Part B of this Section.
Sump - refitting
21Refer to Part B of this Section.
Flywheel - refitting
22Refer to Part B of this Section. When the
flywheel is bolted in position, refer to Chapter
5 for details and refit the clutch unit.
Auxiliary shaft - refitting
23Refer to Part C of this Section.
Cylinder head - refitting
24Refer to Part B of this Section. Note that
this procedure describes cylinder head
refitting complete with the camshaft housingassembly and manifolds as a complete unit.
Details of refitting the camshaft housing (and
followers) to the cylinder head will be found
separately in Part B.
Timing belt and covers -
refitting
25Refer to Part B of this Section.
Engine/transmission -
reconnection and refitting#
Note: A suitable hoist and lifting tackle will be
required for this operation. New locktabs will
be required for the exhaust
downpipe-to-manifold nuts, and suitable
exhaust assembly paste, will be required when
reconnecting the downpipes to the exhaust
manifold.
26Before attempting to reconnect the
engine to the gearbox, check that the clutch
friction disc is centralised as described in
Chapter 5, Section 8. This is necessary to
ensure that the gearbox input shaft splines
will pass through the splines in the centre of
the friction disc.
27Check that the clutch release arm and
bearing are correctly fitted, and lightly grease
the input shaft splines.
28Mate the engine and gearbox together,
ensuring that the engine adapter plate is
correctly located, and that the gearbox
locates on the dowels in the cylinder block,
then refit the engine-to-gearbox bolts and the
single nut, but do not fully tighten them at this
stage. Ensure that any brackets noted during
Supplement: Revisions and information on later models 13•53
7D.8 Locate the bearing shells into the
main bearing caps . . .7D.7B . . . sliding them into position each
side of the No. 5 main bearing
7DS.14 Tighten the main bearing cap bolts
to the specified torque setting7D.10 Lower the crankshaft into position7D.9 . . . and lubricate the shells
13
7D.7A Locate the thrust washer . . .
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removal are in place under the
engine-to-gearbox bolts. Do not allow the
weight of the gearbox to hang on the input
shaft as it is engaged with the clutch friction
disc.
29Refit the starter motor, ensuring that the
wiring harness bracket is in position on the
top bolt.
30Locate the engine/transmission unit at the
front of the car and move it into position under
the engine compartment. Attach the lifting
sling and hoist as during removal.
31Enlist the aid of an assistant to help
steady the combined units as they are raised
into position and to locate the mountings in
the engine compartment.
32Once they are located, tighten the
mountings to the specified torque settings,
then disconnect the lifting hoist and sling.
33The remainder of the refitting and
reconnection procedures are a reversal of the
removal procedure described in Part C. For
further details on reconnecting the
suspension and driveshaft components,
refer to Chapter 7 and Section 13 of this
Chapter.
34Ensure that the exhaust downpipe-to-
manifold connection is clean and renew the
gasket when reconnecting this joint. Use a
smear of exhaust assembly paste on the jointfaces. Use new lockwashers and tighten the
flange nuts securely.
35Ensure that all fuel and coolant
connections are cleanly and securely made.
36Ensure that all wiring connections are
correct and securely made.
37Top up the engine and transmission oil
levels.
38Refill the cooling system.
39Check that all connections are securely
made, then reconnect the battery negative
lead.
Initial start-up after major
overhaul
40Refer to Chapter 1, Section 45.
8 Cooling system
PART A:
999 AND 1108 CC ENGINES
Description
1The operation and function of the cooling
system is essentially as described in Chapter
2 but note the location of the various
components and the routing of the coolant
hoses in Fig. 13.26.
Maintenance
2Topping-up, draining and refilling
procedures are as for 1116 and 1301 cc
engines in Chapter 2, but note that the
coolant capacity is different (see Specifica-
tions).
Thermostat -
removal and refittingÁ
3The thermostat is located on the left-hand
end of the cylinder head, below the
distributor.
4The thermostat cannot be renewed
independently of its housing and if faulty the
complete assembly must be renewed.
5Drain the cooling system.
6Although the thermostat housing can be
removed directly from the cylinder head,
better access is provided if the distributor is
first withdrawn as described in Section 10 of
this Chapter (photo).
7Disconnect the coolant hose from the
thermostat housing and unscrew the housing
flange bolts. Remove the assembly. Note that
it may be necessary to tap it free with a
plastic-faced or wooden mallet if stuck in
place.
8Remove the gasket and clean the mating
surfaces.
9Use a new gasket and bolt the assembly
into position (photo).
10Reconnect the coolant hose, then fill and
bleed the cooling system.
13•54 Supplement: Revisions and information on later models
Fig. 13.26 Cooling system circuit - 999 and 1108 cc engines (Sec 8A)
1 Coolant pump 2 Thermostat 3 Heater matrix
Fig. 13.27 Cooling system thermostat in open and closed positions - 999 and 1108 cc
engines (Sec 8A)8A.9 Fitting the thermostat housing. Note
the new gasket
8A.6 The thermostat housing (shown with
distributor removal) on the 999 cc engine
Page 182 of 303

10Apply suitable sealant to the threads of
the drain plug, then refit and tighten the plug.
11Dispose of the drained coolant safely, or
keep it in a covered container if it is to be
re-used.
12If required, the system can be flushed
through as described in Section 2 of Chap-
ter 2.
13Before attempting to refill the cooling
system, make sure that all hoses have been
reconnected, that the hoses and clips are in
good condition, and that the clips are tight.
Also ensure that the cylinder block drain plug
has been refitted and tightened. Note that an
antifreeze mixture must be used all year round
to prevent corrosion of the engine
components - refer to Section 3, Chapter 2.
14Open the bleed screw in the top of the
expansion tank (photo).
15Remove the expansion tank cap, and fill
the system by slowly pouring the coolant into
the expansion tank to prevent air locks from
forming.
16Top up the coolant until liquid free from air
bubbles emerges from the radiator bleed
screw orifice, then close the bleed screw.
17Continue topping up until the coolant
reaches the Maximum mark on the expansion
tank.
18Start the engine and run it until it reaches
normal operating temperature, then stop the
engine and allow it to cool. Normal operating
temperature is reached when the cooling fancuts into operation. Feel the radiator top hose
to ensure that it is hot. If cool, it indicates an
air lock in the system.
19Check for leaks, particularly around
disturbed components. Check the coolant
level in the expansion tank, and top up if
necessary. Note that the system must be cold
before an accurate level is indicated. There is
a risk of scalding if the expansion tank cap is
removed whilst the system is hot.
Radiator (and cooling fan)
- removal and refitting Á
20Disconnect the battery negative lead.
21Detach the wiring connectors from the
cooling fan and the fan switch located in the
radiator (photos).
22If preferred, the cooling fan unit can be
removed separately from the radiator, by
undoing the attachment bolts and carefully
withdrawing the unit upwards from the
vehicle. Take care not to damage the radiator
core as it is lifted clear (photo).
23Drain the cooling system as described
earlier in this part of the Section, but note that
it will not be necessary to remove the cylinder
block drain plug.
24Undo the retaining screws and remove
the front grille panel.
25Loosen off the retaining clips and detach
the upper coolant hose and the expansion
hose from the radiator.26Note their direction of fitting, then prise
free the radiator retaining clips. Carefully lift
the radiator from the car.
27Refitting is a reversal of the removal
procedure. Ensure that as the radiator is
lowered into position, it engages in the two
rubber location grommets.
28With the radiator (and cooling fan) refitted,
top up the cooling system as described earlier
in this Section (photo).
Thermostat -
removal and refitting Á
Note: A new thermostat cover gasket must be
used on refitting.
29Drain the cooling system as described
earlier in this Section, but note that there is no
need to drain the cylinder block.
30Disconnect the coolant hoses from the
thermostat cover (situated at the gearbox end
of the cylinder head).
31Unscrew the two thermostat cover
securing bolts, noting that the left-hand bolt
may also secure the HT lead bracket, and
remove the thermostat/cover assembly.
Recover the gasket (photo).
32If faulty, the thermostat must be renewed
complete with the housing as an assembly.
33If desired the thermostat can be tested as
described in Chapter 2.
34Refitting is a reversal of removal, bearing
in mind the following points.
Supplement: Revisions and information on later models 13•57
8C.21B Cooling fan switch wiring
connector8C.21A Cooling fan and wiring connector8C.14 Bleed screw location on top of the
expansion tank (arrowed)
8C.31 Thermostat unit removal on the
1372 cc ie engine (distributor removed for
clarity)8C.28 Topping up the radiator coolant level
on the 1372 cc ie engine. Note orientation
of radiator retaining clip (arrowed)8C.22 Cooling fan to radiator securing bolt
13
Page 183 of 303

35Clean the mating faces of the thermostat
cover and cylinder head, and use a new
gasket when refitting the cover.
36Refill the cooling system as described
earlier in this Section.
Coolant pump -
removal and refittingÁ
Note: A new coolant pump gasket must be
used on refitting. If the pump is found to be
worn it must be renewed as a complete unit as
dismantling and repair is not possible.
37Disconnect the battery negative lead.
38Drain the cooling system as described
earlier in this Section.
39Remove the coolant/alternator drivebelt
as described in the next sub-Section.
40Unscrew the four coolant pump securing
bolts, noting that two of the bolts also secure
the alternator adjuster bracket, and withdraw
the pump from the housing (photo). Recover
the gasket.
41Refitting is a reversal of removal, bearing
in mind the following points.
42Use a new gasket between the pump and
the housing.
43Refit and tension the coolant
pump/alternator drivebelt as described in the
next sub-Section.
44On completion, refill the cooling system
as described earlier in this Section.
Coolant pump/alternator
drivebelt - checking,
renewal and tensioning
Á
45At the intervals specified in Section 3 or
“Routine maintenance” at the beginning of
this manual (as applicable), the drivebelt
should be checked and if necessary
re-tensioned.
46Access to the drivebelt is made from the
underside of the car on the right-hand side.
Loosen off the front right-hand roadwheel
retaining bolts, then raise and support the car
on axle stands at the front. Remove the front
roadwheel on the right-hand side.
47Remove the underwing shield from the
right-hand wheel arch by drifting the
compression pins out from the retaining
clips. Prise free the clips and remove the
shield.
48Additional, though somewhat restricted,
access can be obtained from above by
removing the air cleaner unit on the non-Turbo
ie-engine (photo).
49Check the full length of the drivebelt for
cracks and deterioration. It will be necessary
to turn the engine in order to check the
portions of the drivebelt in contact with the
pulleys. If a drivebelt is unserviceable, renew it
as follows (photo).
50Loosen the alternator mounting and
adjuster nuts and bolts and pivot the
alternator towards the cylinder block.51Slip the drivebelt from the alternator,
coolant pump and crankshaft pulleys.
52Fit the new drivebelt around the pulleys,
then lever the alternator away from the
cylinder block until the specified belt tension
is achieved. Lever the alternator using a
wooden or plastic lever at the pulley end to
prevent damage. It is helpful to partially
tighten the adjuster nut before tensioning the
drivebelt (photo).
53When the specified tension has been
achieved, tighten the mounting and adjuster
nuts and bolts (photo).
PART D: HEATER UNIT- LATER
MODELS
Heater unit -
removal and refitting
Á
1The heater unit is removed complete with
the facia/control panel. Commence by
draining the cooling system as described
previously in this Section.
2Disconnect the battery negative lead.
3Refer to Section 15 of this Chapter for
details and remove the ashtray/cigar lighter
and the auxiliary control panel.
4Undo the upper screw retaining the heater
unit to the facia (see Fig. 13.31).
5Remove the radio from the central facia.
6Undo the retaining screw on each side at
the front of the gear lever console. Prise free
13•58 Supplement: Revisions and information on later models
Fig. 13.31 Removing the heater unit-to-
facia upper retaining screw (Sec 8D)8C.53 Tightening the alternator adjuster
nut8C.52 Fitting a new coolant
pump/alternator drivebelt around the
pulleys
8C.49 Alternator/water pump drivebelt and
tensioner viewed from the right-hand
wheel arch8C.48 Top side view of water pump,
alternator and drivebelt8C.40 Coolant pump/alternator bracket
bolt removal
Page 184 of 303

the trim cover, undo the retaining screw at the
rear of the console. Prise free and release the
gear lever gaiter and lift clear the central
console.
7Undo the retaining screws and remove the
steering column upper and lower shroud.
8Detach and remove the lower facia trim on
the side of the central facia.
9Referring to Fig. 13.32, unscrew and
remove the four heater facia to main facia
retaining screws from the points indicated.
10Undo the two retaining nuts securing the
heater to the body on the driver’s side.
11Undo the retaining screws and remove
the pipe shield from the side of the heater
unit, then disconnect the coolant supply and
return hoses from the heater. As the hoses are
detached, be prepared to catch any remainingcoolant as it flows from the hoses and heater
connections.
12Undo the remaining two heater unit
securing nuts and withdraw the heater unit
from the car. As the unit is removed, detach
the wiring and position the hoses with their
ends pointing upwards to avoid further
coolant spillage.
13Refit in the reverse order of removal.
Ensure that the hoses are securely
reconnected. Top up the cooling system on
completion.
Heater unit - dismantling
and reassemblyÁ
14Remove the heater unit as described
previously.
15Pull free the heater/fresh air and blower
control knobs (photo).
16Undo the two retaining screws and
withdraw the control panel from the facia.
Detach the wiring connectors from the panel
illumination lights and remove the panel.17Unscrew the retaining bolts and remove
the centre panel from the heater unit.
18Undo the retaining screws and remove
the control lever mounting.
19Loosen off the grub screws and detach
the cables from the control levers.
20Undo the retaining screws and remove
the control valve.
21Undo the two retaining screws and
withdraw the heater matrix from the heater
housing.
22To separate the casing halves, drill out the
pop rivet securing the mounting bracket,
release the retaining clips and unscrew the
securing bolts.
23Reassemble in the reverse order of
dismantling. Check that the control cables are
correctly adjusted and that the controls
operate in a satisfactory manner before
refitting the heater unit to the car.
Supplement: Revisions and information on later models 13•59
8D.15 Pull free the heater/fresh air and
blower control knobs
Fig. 13.33 Heater pipe shield securing
screw positions on later models (Sec 8D)
Fig. 13.32 Heater unit facia to main facia
retaining screw locations (arrowed)
(Sec 8D)
Fig. 13.34 Heater unit components on later models (Sec 8D)
1 Coolant inlet tap 2 Centre panel 3 Side casings 4 Heater matrix 5 Blower fan
13
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15Release the clamp screw and pinch-bolt,
and disconnect the choke cable.
16Slacken the throttle cable by releasing the
locknut and turning the adjuster sleeve, then
slip the cable nipple out of the notch in the
throttle spindle quadrant.
17Disconnect the lead from the idle cut-off
solenoid valve.
18Unscrew the two long mounting bolts and
lift the carburettor from the inlet manifold
(photo).
19Refitting is a reversal of removal, but
observe the following points (photo).
a) Use a new flange gasket at each side of
the insulator block.
b) Check that the choke cable is fitted so
that full choke can be obtained but the
choke is fully off when the choke control
lever is pushed right in.
c) Adjust the throttle cable so that there is
just a slight amount of slackness when the
accelerator pedal is released, but when
fully depressed, full throttle can be
obtained (throttle valve plate quadrant up
against its stop).
Carburettor (Weber 32
TLF) - overhaul¢
20It is rare for a carburettor to require
complete overhaul and if the unit has seen
considerable service and wear is detected in
the throttle valve spindle bushes, it is
recommended that a new or rebuilt carburet-
tor is obtained.21Normally, the following operations are all
that will be required to keep the carburettor
working perfectly. The unit need not be
removed from the manifold unless the throttle
block is to be detached; simply remove the air
cleaner.
22Periodically, unscrew the large hexagonal
plug adjacent to the fuel inlet pipe, extract the
filter and clean it. Refit the filter and plug
(photo).
23Obtain a repair kit for your carburettor
which will contain all the necessary
replacement gaskets and seals. Extract the top
cover and choke diaphragm assembly fixing
screws, remove the small plastic cover and
push out the bush, then lift the top cover from
the carburettor. Discard the gasket (photos).24Mop out fuel and sediment from the float
chamber.
25The various jets and calibrated bleeds can
then be removed and cleared by blowing
them through with air from a tyre pump. Do
not attempt to clear them by probing with
wire, as this will ruin the calibration.
26Check the tightness of the fuel inlet
needle valve. If necessary, remove the float
and its pivot pin so that a close-fitting ring
spanner can be used on the valve body. Take
care to support the pivot pin pedestals as the
pin is tapped out - they are brittle. The throttle
valve plate block can be removed after
extracting the screws (photos).
27As reassembly progresses, carry out the
following checks and adjustments.
Supplement: Revisions and information on later models 13•63
9B.22 Fuel filter removal from the Weber
32 TLF carburettor9B.19 Carburettor insulator block9B.18 Removing the Weber 32 TLF
carburettor by gripping air cleaner
mounting bracket
9B.26B Fuel inlet valve needle removal
from the Weber 32 TLF carburettor9B.26A Floats and pivot pin arrangement
on the Weber 32 TLF carburettor
9B.23B Disconnecting the choke linkage
on the Weber 32 TLF carburettor9B.23A Choke linkage cover removal from
the Weber 32 TLF carburettor
9B.23C Underside view of the cover on the
Weber 32 TLF carburettor
13
Page 191 of 303

adjustments described in this sub-Section,
however, will require removal of the
carburettor.
39Disconnect the short, curved diaphragm
hose from the top cover.
40Extract the top cover screws, lift the cover
from the carburettor body, and rotate it in
order to release the cranked choke control
rod from its key hole (photo). Mop out the fuel
and clean the jets.
41Check the jet sizes and other components
against those listed in the Specifications, in
case a previous owner has substituted
incorrect components (photo).
42Overhaul procedures are generally as
given in Chapter 3, Section 14 for the Weber
30/32 DMTR, but use the Specifications listed
in this Chapter. Additional overhaul
procedures are given here.
Fuel inlet needle valve
43If a high float level causing flooding of the
carburettor has been evident, first check that
the inlet valve housing is tight, and its washer
is sealing satisfactorily. A leak here will cause
fuel to bypass the inlet valve.
44If the needle valve is to be renewed,
remove it in the following way.
45Access to the fuel inlet needle valve is
obtained by carefully tapping out the float arm
pivot pin. Take care, the pivot pin pillars are
very brittle (photo).
46Unscrew the fuel inlet valve body and
remove the valve and washer.47When refitting the new valve, always use a
new sealing washer.
Float stroke (travel) - see Fig. 3.10
48The float stroke should be between 42.5
and 43.5 mm when measured from the top
cover gasket. Adjust if necessary by bending
the tab on the end of the arm.
Accelerator pump
49Adjustment of the accelerator pump is
very rarely required, but if performance is
suspect, carry out the following operations.
50Fill the carburettor float chamber and then
operate the throttle valve plate lever several
times to prime the pump.
51Position a test tube under the accelerator
pump jet and give ten full strokes of the
throttle lever, pausing between each stroke to
allow fuel to finish dripping.
52The total volume of fuel collected should
be as specified. Adjust the nut on the pump
control if necessary to increase or decrease
the volume of fuel ejected.
General
53When the stage is reached where the
valve plate spindle bushes have worn, then
the carburettor should be renewed complete.
54When reassembling the carburettor, use
new gaskets which can be obtained in a repair
pack.
Carburettor (Weber 32 ICEV
61/250 and DMTE 30/32,
DMTE 30/150) - general
55These carburettor types are fitted to later
models according to engine type. They are
similar in structure and operation to their
equivalents described in Chapter 3. Reference
can therefore be made to that Chapter for the
description and any operations concerning
them, but refer to Section 2 of this Chapter for
their specifications.
Carburettor (Solex
C 30/32-CIC 8) - description
56This carburettor is fitted as an alternative
to the Weber unit on 1116 cc models
produced for certain markets. The removal,
refitting and overhaul procedures are
essentially the same as described earlier for
the Weber carburettors.
PART C:
BOSCH LE2-JETRONIC
FUEL INJECTION SYSTEM
Description
Warning: Refer to the beginning
of this Section before starting
any work.
1The Bosch LE2-Jetronic fuel injection
system, fitted to the 1301 cc Turbo ie model,
is an electronically controlled multi-point
injection (MPi) system.
2The fuel injectors are fed at constant
pressure in relation to inlet manifold vacuum
pressure.
3The system electronic control unit (ECU)
actuates the injectors for variable duration,
and so supplies the precise volume of fuel
required for any given engine speed and load
condition.
4The ECU also monitors the air induction, air
temperature, coolant temperature and throttle
opening as additional parameters to compute
the required opening of the fuel injectors,
giving maximum power with fuel economy.
Fuel supply system
5The fuel supply system consists of an
electric pump and primary filter, located
adjacent to the fuel tank. A fuel pressure peak
damper is located next to the pump (photo).
6Fuel is then pumped through a filter to the
fuel rail and injectors. The injectors are of the
13•66 Supplement: Revisions and information on later models
9C.5 Electric fuel pump/filter/pressure
damper assembly location on a 1301 cc
Turbo ie model
9B.41 Jets on the Weber 30/32 DMTE
carburettor (top cover removed)
9B.45 Float pivot arrangement and needle
valve on the Weber 30/32 DMTE
carburettor
9B.40 Unscrewing a top cover screw from
the Weber 30/32 DMTE carburettor9B.37F Unscrewing a carburettor fixing nut
Page 192 of 303

solenoid-operated type, actuated from the
ECU.
7Fuel pressure is regulated according to inlet
manifold vacuum pressure by a fuel pressure
regulator. Excess unpressurised fuel is
returned to the fuel tank.
Airflow meter
8This component measures the quantity of
air drawn into the engine, and converts this
into an electric signal which is transmitted to
the ECU.
9The intake air exerts a force on the floating
plate (1) (Fig. 13.39) which is connected to a
potentiometer (2).
10A compensating butterfly valve (3)
compensates for any reflex pressure which
may occur, and is subject to the braking effect
of the damper chamber (4).
11The idle mixture (air/fuel ratio) is altered by
means of the screw (8), which alters the
cross-section of the bypass channel (7).
12An integral-type temperature sensor is
fitted, the resistance value of which decreases
as the temperature of the intake air increases.
This facility is used to correct the mixture
strength within a pre-determined air
temperature range.
Throttle valve housing
13The housing incorporates a conventional
butterfly-type throttle valve, actuated by
cables and rods from the accelerator pedal.
14The idle bypass channel (2) (Fig. 13.40) is
fitted with an adjustment screw (3) to vary the
idle speed.
15The other screw (4) and locknut are usedto set the closing position of the throttle valve
plate.
Supplementary air valve
16This controls the air volume requirement
during cold starting. Essentially, the valve is an
electrically-heated bi-metallic strip, which rotates
the plate (4) (Fig. 13.41) to vary the volume of air
being drawn in through the aperture (1),
according to the temperature of the engine.
17The requirement for additional air during
cold starting is to dilute the additional fuel,
which is injected and controlled by the ECU
as a result of monitoring the engine coolant
temperature sensor.
Electrical control circuit
18The main components of the system are
the ECU and the system control relay. The
relay incorporates a fuel cut-off facility, which
cuts off the fuel supply in the event of engine
failure, the vehicle turning over, or a fuel line
breaking. The relay energises the following
electrical components.
19Coolant temperature sensor, which
signals the coolant temperature to the ECU.
20Throttle position switch, which signals the
ECU when the throttle valve plate is closed, in
order to actuate the deceleration fuel cut-off
device at speeds above 2500 rpm.21The switch also signals the ECU at full
throttle, so that the mixture can be enriched to
cope with full-power requirements.
22The system control relay also monitors the
engine speed directly from the ignition coil
primary winding.
MaintenanceÁ
23Regularly check the security of all system
hoses, wiring connections and plugs.
24At the intervals specified in Section 3,
renew the fuel filter and the air cleaner element.
Fuel filter - renewalÁ
25This is located within the engine
compartment just above the timing belt cover.
Disconnect the fuel hoses, but be prepared
for loss of fuel (photo).
26When fitting the new filter, make sure that
the arrow stamped on it is pointing towards
the fuel injector rail.
Air cleaner element -
renewal
Á
27Prise back the toggle-type clips and take
off the air cleaner lid. Remove and discard the
element, and wipe any dirt from the inside of
the casing (photos).
28Fit the new element and replace the lid.
Supplement: Revisions and information on later models 13•67
Fig. 13.41 Supplementary air valve -
1301 cc Turbo ie engine (Sec 9C)
1 Aperture
2 Bi-metallic strip
3 Passage
4 Rotating plate (closed position)Fig. 13.40 Sectional view of throttle valve
housing - 1301 cc Turbo ie engine (Sec 9C)
1 Butterfly-type throttle valve
2 Idle bypass channel
3 Idle speed adjusting screw
4 Throttle valve plate setting screwFig. 13.39 Sectional view of airflow meter -
1301 cc Turbo ie engine (Sec 9C)
1 Floating plate
2 Potentiometer
3 Compensating butterfly valve
4 Damper chamber
6 Spring
7 Bypass channel
8 CO adjusting screw
9 Tamperproof plug
Terminals
5, 7, 8, Potentiometer
9 Air temperature sensor
E Sealed (not to be touched)
9C.27A Removing the air cleaner lid9C.25 Secondary fuel filter
13
Page 193 of 303

Idle speed and mixture
adjustment¢
29Before carrying out any adjustments, the
engine must be at operating temperature, the
fan having cut in at second speed and then
switched off.
30Release the locknut and turn the main idle
speed screw in the throttle valve housing until
the engine idles at the specified speed. This
should be all that is necessary to obtain the
correct idle speed, as the throttle valve plate
base setting is set during production.
However, if wear has taken place, or incorrect
adjustment has been carried out previously,
proceed in the following way.
31Disconnect the intake duct from the
throttle valve housing. Release the locknut on
the base (small) adjusting screw, and turn thescrew until there is a clearance between the
lower edge of the throttle valve plate and the
throat wall of between 0.05 and 0.1 mm
(photos).
32With the engine still at operating
temperature, start the engine, and having
released the locknut, turn the main (large) idle
speed screw fully clockwise to close the
bypass passage.
33Now turn the base (small) screw until the
engine idles at between 700 and 800 rpm.
Tighten the locknut.
34Finally, turn the main (large) adjusting
screw to give an idle speed of between 800
and 900 rpm.
35It is unlikely that the mixture will require
alteration, but if it does, connect an exhaust
gas analyser to the car in accordance with the
equipment manufacturer’s instructions.
36With the engine at operating temperature,
prise out the tamperproof cap, and turn the
mixture screw, which is located in the airflow
meter, until the CO level is as given in the
Specifications. Turning the screw clockwise
richens the mixture, turning it anti-clockwise
weakens the mixture. Use a close-fitting Allen
key for the adjustment (photo).
Fuel injection system -
electrical testsª
37When carrying out checks to trace a fault
in the system, an ohmmeter should be used
for the following tests.
38Disconnect the multipin connector from
the ECU, and also the one from the system
control relay, and apply the probes of the
ohmmeter in accordance with the following
sequence to check for continuity in thecables. The component wiring plug will of
course be disconnected for the test.
ECU connector Component connector
plug terminal plug terminal
1 1 of ignition coil
2 2 of throttle position
switch
3 3 of throttle position
switch
4 50 of ignition switch
5 Earth
5 5 of airflow meter
7 7 of airflow meter
8 8 of airflow meter
9 9 of airflow meter
9 9 of throttle position
switch
9 18 of supplementary air
valve
9 87 main relay socket
10 10 of coolant temperature
sensor
12 Injector terminals
13 Earth
System control Component connector
relay connector plug terminal
plug terminal
1 1 of ignition coil
15 15 of ignition switch
30 Battery positive
31 Earth
50 50 of ignition switch
87 Injector terminals
87 18 of throttle position
switch
87 9 of ECU multipin socket
87b Fuel pump (fused)
13•68 Supplement: Revisions and information on later models
Fig. 13.42 ECU and component connector plug terminals - 1301 cc Turbo ie engine (Sec 9C)
For colour code see main wiring diagrams
9C.31C Checking throttle valve plate
opening with a feeler blade
9C.36 Using an Allen key to adjust the
mixture (CO level)
9C.31B Idle speed base setting screw (1)
and main adjustment screw (2)9C.31A Disconnecting the throttle valve
housing intake duct9C.27B Removing the air cleaner element
Page 197 of 303

Throttle position switch
(potentiometer)
90This is located on the left side of the
throttle valve housing (photo).
91Disconnect the wiring plug, unscrew the
two fixing screws and withdraw the switch.
Fuel filter
92Unscrew the fuel line banjo unions from
the filter, which is located in the right-hand
rear corner of the engine compartment. Be
prepared for some loss of pressurised fuel,
and mop it up with rags.
Fuel pump
93The fuel pump can be removed from its
location beside the fuel tank afterdisconnecting the fuel hoses and wiring plug,
and then releasing the mounting clamp.
Refitting all components
94Refitting of all components is a reversal of
removal, but observe the following points.
95Use new seals and gaskets as applicable,
noting that three rubber seals are used on
each fuel injector and insulator (photos).
96Adjust the throttle position switch as
described in paragraph 46 of this Section.
97When refitting a new fuel filter, make sure
that the arrow marked on it is in the direction
of the fuel flow.
98Apply gasket cement to the threads of the
coolant temperature sensor.
Throttle control linkage -
general
99This is of the cable and rod type. Adjust the
cable by means of the end fitting and nut, to give
the slightest play in the cable when the plastic
socket is engaged with the ball on the link rod
which runs across the camshaft cover (photos).
100Keep the cross-shaft pivots and return
springs lubricated.
Fuel tank - general
101The fuel tank is of metal construction, but
note the plastic anti-blow-back compartment
between the filler cap and the tank. This is
accessible from under the right-hand wheel
arch (photo).
13•72 Supplement: Revisions and information on later models
9C.99B Throttle cable (secondary section)
and cross-shaft9C.99A Throttle cable and end fitting
(primary section)9C.95D Inlet pipe stub gasket
9C.95C Fuel injector insulator seal9C.95B Fuel injector small seal9C.95A Fuel injector large seal
9C.90 Throttle position switch (wiring plug
arrowed)9C.88B Supplementary air valve (arrowed)9C.88A Disconnecting the supplementary
air valve hose from the inlet manifold