1983 FIAT UNO clock setting

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

operation twice. Also prior to making
adjustments ensure that the supplementary
air valve pipe is in good condition, with no
leaks. Compress the air valve pipe using a
pair of grips to prevent incorrect adjustment
caused by a defective supplementary air
valve.
15The air cleaner must be connected when
checking and/or adjusting the engine idle
speed. To adjust, turn the adjuster screw in
the required direction to set the engine idle
speed to that specified.
16It is unlikely that the mixture will require
adjustment and unless this is proven by
measuring the exhaust gases using a CO
content analyser, its setting should not be
altered. As with idle speed adjustment, the
engine must be at its normal operating
temperature when making this check and
adjustment. It is also necessary to ensure that
the ignition idle advance is as specified.
Checking and adjustment must not be made
with the engine cooling fan, air conditioning
(where fitted) or other related items switched
on.
17If adjustment to the mixture is required,
prise free the tamperproof plug from the front
of the mixture adjustment screw in the control
unit, then turn the screw as required. Turn the
screw inwards (clockwise) to increase the CO
content or outwards (anti-clockwise) to
weaken it.
Throttle position switch adjustment
18This switch will not normally require
adjustment having been set during
production. The switch should not be
loosened off or reset unless absolutely
necessary.
19If a new switch is fitted it can be set by
loosely fitting the securing bolts, turning the
switch fully anti-clockwise, then clockwise
until one of the internal contacts is felt to click
into engagement. Hold the switch in this
position and tighten the retaining screws.
Reconnect the wiring multiplug to the switch.
Accelerator cable adjustment
20If the accelerator cable is removed or
detached from the support bracket at the
throttle control housing at any time, care must
be taken to adjust it correctly. When the inner
cable is connected to the throttle quadrant,
set the outer cable in the bracket so that the
inner cable has a minimal amount of free play,
yet does not prevent the throttle valve from
fully closing.
21When the engine is restarted, check that
the engine idle speed is as specified and that
the action of the accelerator is satisfactory.
Fuel pump and supply system checks
22Although the following basic checks can
be made to the fuel pump and fuel supply
system, specialised equipment is required to
undertake full and accurate tests of the fuel
supply system. Such checks must therefore
be entrusted to a FIAT dealer or a fuel
injection specialist.
23If the fuel pump is suspected of
malfunction, a basic check can be made by
turning the ignition on and listening around
the area of the pump unit to hear if it is
operating. The pump is located on the
underside of the car, just forward of the fuel
tank. If the pump fails to operate, check thatthe pump fuse is sound and that its
connection (and also that the relay) are clean
and secure.
24The pump can be further checked as
described previously for the LE2 fuel injection
system fuel pump in Part C of this Section.
Supplementary air valve check
25With the engine at its normal operating
temperature, allow it to idle, then pinch the
supplementary air valve hose using suitable
pliers as shown in Fig. 13.52 and check to see
if the engine speed drops by more than 50
rpm. If it does, the supplementary air valve is
defective and in need of renewal.
Injection system
components -
removal and refitting
Á
Warning: Refer to the beginning
of this Section before starting
any work.
26With the exception of the items mentioned
below, the various components of the fuel
injection system are removed in the same
manner as that described for the equivalent
items in Part C of this Chapter.
27Disconnect the battery negative lead
before carrying out any of the removal and
refitting operations. Where fuel lines are to be
disconnected it will first be necessary to
depressurise the injection system.
Airflow meter
28Release the retaining clips and detach the
air intake and outlet ducts from the airflow
meter.
29Ensure that the ignition is switched off,
then disconnect the multiplug from the ECU.
Unscrew the retaining bolts and remove the
airflow meter complete with the ECU.
30If required, the ECU can be separated
from the airflow meter by undoing the
securing bolts.
Throttle valve housing/inlet manifold
31Loosen off the retaining clip and detach
the air intake duct from the throttle housing,
the air cooling hoses for the injectors and the
supplementary air valve.
32Detach the accelerator cable from the
throttle linkage.
13•80 Supplement: Revisions and information on later models
Fig. 13.56 Disconnecting the injector air
cooling hoses and the supplementary air
valve hose on the 1372 cc Turbo ie engine
(Sec 9E)Fig. 13.55 Disconnecting the air intake
duct and accelerator cable from the
throttle housing on the 1372 cc Turbo ie
engine (Sec 9E)
Fig. 13.54 Accelerator cable adjustment
on the 1372 cc Turbo ie engine (Sec 9E)
1 Adjuster 3 Quadrant support
2 Inner cableFig. 13.53 Mixture adjustment screw
location on the 1372 cc Turbo ie engine
(Sec 9E)

Starter motor brushes
(later models) - renewal#
25When renewing the starter motor brushes
on later models, the old brushes will need to
be crushed (in a vice or with a hammer) and
their leads then soldered to the new brushes.
Fuses - later models
26The fuse arrangement is slightly different
on later models, but the circuits protected are
still identified by a symbol. Refer to the
Specifications Section for full details. Note
also the terminal block with plastic cover,
which can be used to isolate the battery from
the electrical system by disconnecting the
leads from the terminals (photos).
Relays (Turbo ie models) -
general
27On Turbo ie models, the relays mounted
in the fuse block are as shown in Fig. 13.103.
Additional relays are located as follows:
Headlamp relay - on lead under main fuse
blockFuel injection system main control relay -
adjacent to airflow meter
Headlamps later models
28The headlamp units fitted on later models
differ according to model, but the bulb and
unit replacement details are generally the
same as described for previous models in
Chapter 9. Note that the rubber cover can
only be fitted with the tab to the top as shown
(photo).
Headlamp beam adjusters for
load compensation - later
models
29Some later models are fitted with
headlamp beam adjusters which allowtemporary resetting to be made (such as
when the car is fully loaded). Access to these
adjusters is made by lifting the bonnet (photo).
30Turn the adjusters anti-clockwise to lower
the beam to the normal level or clockwise to
raise the beam (when the car is unloaded).
Repeat the procedure on the opposite
headlamp unit an equal amount.
31Other later models have separate
horizontal and vertical beam adjusters,
positioned as shown (photos). A load
compensating lever is attached to the
adjusters to enable temporary resetting of the
headlamp beams, without changing the
normal adjustment. Turn the lever to the
appropriate side (right or left) to make the
adjustment as required. The normal setting
Supplement: Revisions and information on later models 13•105
15.26B Battery lead terminal block on the
1301 cc Turbo ie model15.23B Starter motor and wiring
connections on the 1372 cc ie engine
15.31B Headlamp vertical beam alignment
adjuster screw on a 1372 cc ie model. Note
the load compensator lever which is set in
the “O” (normal load) setting position15.31A Headlamp horizontal beam
alignment adjuster screw on a 1372 cc ie
model
15.29 Headlamp beam adjuster on the
999 cc Turbo ie model15.28 Headlamp unit fitted to the 1372 cc ie
model
15.26A Fuse block on the 1301 cc Turbo ie
model
13
Fig. 13.103 Auxiliary fuses and relays on
1301 cc Turbo ie models (Sec 15)
1 Horn relay
2 Heated rear screen relay
3 Foglamps relay
4 Radiator fan relay
5 Electric windows relay
6 Foglamps fuse
7 Radiator fan second speed fuse
8 Fuel injector fan fuse
9 Electric windows fuse
10 Electric fuel pump fuse