1990 BMW 5 SERIES ignition

indicates that the direction indicator and/or
hazard fuse has blown, check the wiring for a
short-circuit before fitting a new fuse.
4Make sure that the new unit is identical to
the original. Compare the old one to the new
one before fitting it.
5Refitting is the reverse of removal.
6 Steering column switches-
removal and refitting
1
Warning: Some later models are
equipped with an airbag or
Supplemental Restraint System
(SRS). To avoid possible damage
to this system, the manufacturer
recommends that, on airbag-equipped
models, the following procedure should be
left to a dealer service department, or
other specialist, because of the special
tools and techniques required. There is a
risk of injury if the airbag is accidentally
triggered.
Caution: If the radio in your
vehicle is equipped with an anti-
theft system, make sure you have
the correct activation code
before disconnecting the battery, Refer to
the information on page 0-7 at the front of
this manual before detaching the cable.
Note: If, after connecting the battery, the
wrong language appears on the instrument
panel display, refer to page 0-7 for the
language resetting procedure.
1Disconnect the battery negative cable,
remove the steering wheel (see Chapter 10)
and steering column shrouds (see Chapter 11).
Direction indicator/headlight
switch
2Where necessary, remove the switch
mounting screws. Depress the tabs and pull
the switch out of the steering column
mounting (see illustration).
3Trace the switch wires down the steering
column to the electrical connector, and
unplug them (see illustration).
4Refitting is the reverse of removal.
Wiper/washer switch
5Where necessary, remove the switch
mounting screws.
6Depress the release clip, and detach the
switch from the steering column mounting
(see illustration). Trace the switch wiring
down the steering column to the electrical
connector, and unplug it.
7Refitting is the reverse of removal.
Cruise control switch
8Remove the wiper/washer switch.
9Where necessary, remove the switch
mounting screw. Squeeze the release tabs,
and withdraw the switch from the mounting
(see illustration).
10Disconnect the switch electrical
connector from the harness at the base of the
steering column.
11Refitting is the reverse of removal.
7 Ignition switch-
removal and refitting
1
Warning: Some later models are
equipped with an airbag or
Supplemental Restraint System
(SRS). To avoid possible damage
to this system, the manufacturer
recommends that, on airbag-equipped
models, the following procedure should be
left to a dealer service department, or
other specialist, because of the specialtools and techniques required. There is a
risk of injury if the airbag is accidentally
triggered.
Caution: If the radio in your
vehicle is equipped with an anti-
theft system, make sure you have
the correct activation code
before disconnecting the battery, Refer to
the information on page 0-7 at the front of
this manual before detaching the cable.
Note: If, after connecting the battery, the
wrong language appears on the instrument
panel display, refer to page 0-7 for the
language resetting procedure.
Removal
1Disconnect the battery negative cable.
2Remove the steering wheel (see Chap-
ter 10).
3Remove the steering column shrouds (see
Chapter 11).
4Where necessary, remove the direction
indicator/headlight control switch (see Sec-
tion 6).
5Detach the clips by inserting a small
screwdriver into the openings on the sides
while pulling out on the switch (see
illustration).
6Unplug the electrical connector from the
harness at the base of the steering column,
and remove the switch.
Refitting
7Refitting is the reverse of removal.
Body electrical systems 12•3
6.3 Follow the wiring down the steering
column to the connector6.2 Squeeze the tabs to release the switch
from the mounting
6.9 Cruise control switch removal6.6 Squeeze the wiper/washer switch tabs
and pull it directly out of the mounting
12
5.1 The direction indicator/hazard warning
flasher unit is located on the steering
column on most models - squeeze the
tabs to detach it

12Refitting is a reversal of removal. When
fitting the motor, if necessary plug in the
connector and run the motor briefly until it is
in the “neutral” (wiper parked) position.
17 Heated rear window-
check and repair
2
1The heated rear window consists of a
number of horizontal elements on the glass
surface.
2Small breaks in the element can be repaired
without removing the rear window.
Check
3Switch on the ignition and the heated rear
window.
4Place the positive lead of a voltmeter to the
heater element nearest to the incoming power
source.
5Wrap a piece of aluminium foil around the
negative lead of the voltmeter on the positive
side of the suspected broken element, and
slide it slowly towards the negative side.
Watch the voltmeter needle - when it moves
from zero, you have located the break.
Repair
6Repair the break in the line using a repair kit
recommended specifically for this purpose,
such as BMW repair kit No. 81 22 9 (or
equivalent). Included in this kit is plastic
conductive epoxy. The following paragraphs
give general instructions for this type of repair;
follow the instructions supplied with the repair
kit if they are different.
7Prior to repairing a break, switch off the
circuit and allow it to cool down for a few
minutes.
8Lightly buff the element area with fine steel
wool, then clean it thoroughly.
9Use masking tape to mask off the area of
repair, leaving a slit to which the epoxy can be
applied.
10Mix the epoxy thoroughly, according to
the instructions on the package.
11Apply the epoxy material to the slit in the
masking tape, overlapping the undamaged
area about 20 mm on each end.12Allow the repair to cure for 24 hours
before removing the tape and using the
heated rear window.
18 Supplemental Restraint
System (SRS)- general
information
Later models are equipped with a
Supplemental Restraint System (SRS),
incorporating an airbag. This system is
designed to protect the driver from serious
injury in the event of a head-on or frontal
collision. It consists of an airbag module in the
centre of the steering wheel, two crash
sensors mounted on the front inner wing
panels, and a crash safety switch located
inside the passenger compartment.
The airbag module contains a housing
incorporating the airbag and the inflator units.
The inflator assembly is mounted on the back
of the housing over a hole through which gas
is expelled, inflating the bag almost instanta-
neously when an electrical signal is sent from
the system. This signal is carried by a wire
which is specially wound with several turns,
so the signal will be transmitted regardless of
the steering wheel position.
The SRS system has three sensors: two at
the front, mounted on the inner wing panels
(see illustration), and a safety switch located
inside the passenger compartment. The crash
sensors are basically pressure-sensitive
switches, which complete an electrical circuit
during an impact of sufficient force. The
electrical signal from the crash sensors is sent
to a third sensor, which then completes the
circuit and inflates the airbag.
The module containing the safety switch
monitors the system operation. It checks the
system every time the vehicle is started,
causing the AIRBAG warning light to come on,
then go out if the system is operating
correctly. If there is a fault in the system, the
light will stay on. If the AIRBAG warning light
does stay on, or if it comes on while driving,
take the vehicle to your dealer immediately.
19 Cruise control system-
description and check
1
The cruise control system maintains vehicle
speed using a vacuum-actuated servo motor
located in the engine compartment, which is
connected to the throttle linkage by a cable.
The system consists of the servo motor,
clutch switch, brake switch, control switches,
a relay, and associated vacuum hoses.
Because of the complexity of the cruise
control system, repair should be left to a
dealer service department. However, it is
possible for the home mechanic to make
simple checks of the wiring and vacuum
connections for minor faults which can be
easily repaired. These include:
a) Inspect the cruise control actuating switches
for broken wires and loose connections.
b) Check the cruise control fuse.
c) The cruise control system is operated by
vacuum, so it’s critical that all vacuum
switches, hoses and connections are
secure. Check the hoses in the engine
compartment for loose connections,
cracks, or obvious vacuum leaks.
20 Central locking system-
description and check
2
The central door locking system operates
the door lock actuators mounted in each
door. The system consists of the switches,
actuators and associated wiring. Diagnosis is
limited to simple checks of the wiring
connections and actuators for minor faults
which can be easily repaired. These include:
a) Check the system fuse and/or circuit
breaker (where applicable).
b) Check the switch wires for damage and
loose connections. Check the switches
for continuity.
c) Remove the door trim panel(s), and check
the actuator wiring connections to see if
they’re loose or damaged. Inspect the
actuator rods to make sure they aren’t
12•8 Body electrical systems
18.3 The SRS system crash sensors
(arrowed) are located in the engine
compartment - check the wiring regularly
for damage16.11b Tailgate wiper motor (5-Series)16.11c Wiper blade and pivot mechanism
on the rear window (5-Series)

REF•2MOT Test Checks
Seat belts and seats
Note: The following checks are applicable to
all seat belts, front and rear.
MExamine the webbing of all the belts
(including rear belts if fitted) for cuts, serious
fraying or deterioration. Fasten and unfasten
each belt to check the buckles. If applicable,
check the retracting mechanism. Check the
security of all seat belt mountings accessible
from inside the vehicle.
MThe front seats themselves must be
securely attached and the backrests must
lock in the upright position.
Doors
MBoth front doors must be able to be opened
and closed from outside and inside, and must
latch securely when closed.
Vehicle identification
MNumber plates must be in good condition,
secure and legible, with letters and numbers
correctly spaced – spacing at (A) should be
twice that at (B).
MThe VIN plate and/or homologation plate
must be legible.
Electrical equipment
MSwitch on the ignition and check the
operation of the horn.
MCheck the windscreen washers and wipers,
examining the wiper blades; renew damaged
or perished blades. Also check the operation
of the stop-lights.
MCheck the operation of the sidelights and
number plate lights. The lenses and reflectors
must be secure, clean and undamaged.
MCheck the operation and alignment of the
headlights. The headlight reflectors must not
be tarnished and the lenses must be
undamaged.
MSwitch on the ignition and check the
operation of the direction indicators (including
the instrument panel tell-tale) and the hazard
warning lights. Operation of the sidelights and
stop-lights must not affect the indicators - if it
does, the cause is usually a bad earth at the
rear light cluster.
MCheck the operation of the rear foglight(s),
including the warning light on the instrument
panel or in the switch.
Footbrake
MExamine the master cylinder, brake pipes
and servo unit for leaks, loose mountings,
corrosion or other damage.
MThe fluid reservoir must be secure and the
fluid level must be between the upper (A) and
lower (B) markings.MInspect both front brake flexible hoses for
cracks or deterioration of the rubber. Turn the
steering from lock to lock, and ensure that the
hoses do not contact the wheel, tyre, or any
part of the steering or suspension mechanism.
With the brake pedal firmly depressed, check
the hoses for bulges or leaks under pressure.
Steering and suspension
MHave your assistant turn the steering wheel
from side to side slightly, up to the point where
the steering gear just begins to transmit this
movement to the roadwheels. Check for
excessive free play between the steering
wheel and the steering gear, indicating wear or
insecurity of the steering column joints, the
column-to-steering gear coupling, or the
steering gear itself.
MHave your assistant turn the steering wheel
more vigorously in each direction, so that the
roadwheels just begin to turn. As this is done,
examine all the steering joints, linkages,
fittings and attachments. Renew any
component that shows signs of wear or
damage. On vehicles with power steering,
check the security and condition of the
steering pump, drivebelt and hoses.
MCheck that the vehicle is standing level,
and at approximately the correct ride height.
Shock absorbers
MDepress each corner of the vehicle in turn,
then release it. The vehicle should rise and
then settle in its normal position. If the vehicle
continues to rise and fall, the shock absorber
is defective. A shock absorber which has
seized will also cause the vehicle to fail.
2Checks carried out
WITH THE VEHICLE ON THE
GROUND

REF•4MOT Test Checks
MExamine the handbrake mechanism,
checking for frayed or broken cables,
excessive corrosion, or wear or insecurity of
the linkage. Check that the mechanism works
on each relevant wheel, and releases fully,
without binding.
MIt is not possible to test brake efficiency
without special equipment, but a road test can
be carried out later to check that the vehicle
pulls up in a straight line.
Fuel and exhaust systems
MInspect the fuel tank (including the filler
cap), fuel pipes, hoses and unions. All
components must be secure and free from
leaks.
MExamine the exhaust system over its entire
length, checking for any damaged, broken or
missing mountings, security of the retaining
clamps and rust or corrosion.
Wheels and tyres
MExamine the sidewalls and tread area of
each tyre in turn. Check for cuts, tears, lumps,
bulges, separation of the tread, and exposure
of the ply or cord due to wear or damage.
Check that the tyre bead is correctly seated
on the wheel rim, that the valve is sound andproperly seated, and that the wheel is not
distorted or damaged.
MCheck that the tyres are of the correct size
for the vehicle, that they are of the same size
and type on each axle, and that the pressures
are correct.
MCheck the tyre tread depth. The legal
minimum at the time of writing is 1.6 mm over
at least three-quarters of the tread width.
Abnormal tread wear may indicate incorrect
front wheel alignment.
Body corrosion
MCheck the condition of the entire vehicle
structure for signs of corrosion in load-bearing
areas. (These include chassis box sections,
side sills, cross-members, pillars, and all
suspension, steering, braking system and
seat belt mountings and anchorages.) Any
corrosion which has seriously reduced the
thickness of a load-bearing area is likely to
cause the vehicle to fail. In this case
professional repairs are likely to be needed.
MDamage or corrosion which causes sharp
or otherwise dangerous edges to be exposed
will also cause the vehicle to fail.
Petrol models
MHave the engine at normal operating
temperature, and make sure that it is in good
tune (ignition system in good order, air filter
element clean, etc).
MBefore any measurements are carried out,
raise the engine speed to around 2500 rpm,
and hold it at this speed for 20 seconds. Allowthe engine speed to return to idle, and watch
for smoke emissions from the exhaust
tailpipe. If the idle speed is obviously much
too high, or if dense blue or clearly-visible
black smoke comes from the tailpipe for more
than 5 seconds, the vehicle will fail. As a rule
of thumb, blue smoke signifies oil being burnt
(engine wear) while black smoke signifies
unburnt fuel (dirty air cleaner element, or other
carburettor or fuel system fault).
MAn exhaust gas analyser capable of
measuring carbon monoxide (CO) and
hydrocarbons (HC) is now needed. If such an
instrument cannot be hired or borrowed, a
local garage may agree to perform the check
for a small fee.
CO emissions (mixture)
MAt the time of writing, the maximum CO
level at idle is 3.5% for vehicles first used after
August 1986 and 4.5% for older vehicles.
From January 1996 a much tighter limit
(around 0.5%) applies to catalyst-equipped
vehicles first used from August 1992. If the
CO level cannot be reduced far enough to
pass the test (and the fuel and ignition
systems are otherwise in good condition) then
the carburettor is badly worn, or there is some
problem in the fuel injection system or
catalytic converter (as applicable).
HC emissionsMWith the CO emissions within limits, HC
emissions must be no more than 1200 ppm
(parts per million). If the vehicle fails this test
at idle, it can be re-tested at around 2000 rpm;
if the HC level is then 1200 ppm or less, this
counts as a pass.
MExcessive HC emissions can be caused by
oil being burnt, but they are more likely to be
due to unburnt fuel.
Diesel models
MThe only emission test applicable to Diesel
engines is the measuring of exhaust smoke
density. The test involves accelerating the
engine several times to its maximum
unloaded speed.
Note: It is of the utmost importance that the
engine timing belt is in good condition before
the test is carried out.
M
Excessive smoke can be caused by a dirty
air cleaner element. Otherwise, professional
advice may be needed to find the cause.
4Checks carried out on
YOUR VEHICLE’S EXHAUST
EMISSION SYSTEM

REF•9
REF
Fault Finding
Engine
m mEngine will not rotate when attempting to start
m mEngine rotates, but will not start
m mEngine hard to start when cold
m mEngine hard to start when hot
m mStarter motor noisy or excessively-rough in engagement
m mEngine starts, but stops immediately
m mOil puddle under engine
m mEngine idles erratically
m mEngine misses at idle speed
m mEngine misses throughout driving speed range
m mEngine misfires on acceleration
m mEngine surges while holding accelerator steady
m mEngine stalls
m mEngine lacks power
m mEngine backfires
m mPinking or knocking engine sounds when accelerating
or driving uphill
m mEngine runs with oil pressure light on
m mEngine runs-on after switching off
Engine electrical system
m
mBattery will not hold charge
m mIgnition (no-charge) warning light fails to go out
m mIgnition (no-charge) warning light fails to come on
when key is turned
Fuel system
m mExcessive fuel consumption
m mFuel leakage and/or fuel odour
Cooling system
m
mOverheating
m mOvercooling
m mExternal coolant leakage
m mInternal coolant leakage
m mCoolant loss
m mPoor coolant circulation
Clutch
m
mPedal travels to floor - no pressure or very little resistance
m mFluid in area of master cylinder dust cover and on pedal
m mFluid on slave cylinder
m mPedal feels “spongy” when depressed
m mUnable to select gears
m mClutch slips (engine speed increases with no increase in
vehicle speed)
m mGrabbing (chattering) as clutch is engaged
m mNoise in clutch area
m mClutch pedal stays on floor
m mHigh pedal effort
Manual transmission
m
mVibration
m mNoisy in neutral with engine running
m mNoisy in one particular gear
m mNoisy in all gears
m mSlips out of gear
m mLeaks lubricant
Automatic transmission
m
mFluid leakage
m mTransmission fluid brown, or has a burned smell
m mGeneral shift mechanism problems
m mTransmission will not kickdown with accelerator pedal
pressed to the floor
m mEngine will start in gears other than Park or Neutral
m mTransmission slips, shifts roughly, is noisy, or has no drive
in forward or reverse gears
Brakes
m mVehicle pulls to one side during braking
m mNoise (high-pitched squeal) when the brakes are applied
m mBrake vibration (pedal pulsates)
m mExcessive pedal effort required to stop vehicle
m mExcessive brake pedal travel
m mDragging brakes
m mGrabbing or uneven braking action
m mBrake pedal feels “spongy” when depressed
m mBrake pedal travels to the floor with little resistance
m mHandbrake does not hold
Suspension and steering
m
mVehicle pulls to one side
m mAbnormal or excessive tyre wear
m mWheel makes a “thumping” noise
m mShimmy, shake or vibration
m mHigh steering effort
m mPoor steering self-centring
m mAbnormal noise at the front end
m mWandering or poor steering stability
m mErratic steering when braking
m mExcessive pitching and/or rolling around corners or
during braking
m mSuspension bottoms
m mUnevenly-worn tyres
m mExcessive tyre wear on outside edge
m mExcessive tyre wear on inside edge
m mTyre tread worn in one place
m mExcessive play or looseness in steering system
m mRattling or clicking noise in steering gear

REF•10Fault Finding
Engine will not rotate when attempting to start
m mBattery terminal connections loose or corroded (Chapter 1).
m mBattery discharged or faulty (Chapter 1).
m mAutomatic transmission not completely engaged in Park (Chap-
ter 7B) or (on models with a clutch switch) clutch not completely
depressed (Chapter 8).
m mBroken, loose or disconnected wiring in the starting circuit
(Chapters 5 and 12).
m mStarter motor pinion jammed in flywheel ring gear (Chapter 5).
m mStarter solenoid faulty (Chapter 5).
m mStarter motor faulty (Chapter 5).
m mIgnition switch faulty (Chapter 12).
m mStarter pinion or flywheel teeth worn or broken (Chapter 5).
m mEngine internal problem (Chapter 2B).
Engine rotates, but will not start
m
mFuel tank empty.
m mBattery discharged (engine rotates slowly) (Chapter 5).
m mBattery terminal connections loose or corroded (Chapter 1).
m mLeaking fuel injector(s), faulty fuel pump, pressure regulator, etc
(Chapter 4).
m mFuel not reaching fuel injection system or carburettor (Chapter 4).
m mIgnition components damp or damaged (Chapter 5).
m mFuel injector stuck open (Chapter 4).
m mWorn, faulty or incorrectly-gapped spark plugs (Chapter 1).
m mBroken, loose or disconnected wiring in the starting circuit
(Chapter 5).
m mLoose distributor mounting bolts causing ignition timing to wander
(Chapters 1 and 5).
m mBroken, loose or disconnected wires at the ignition coil, or faulty
coil (Chapter 5).
Engine hard to start when cold
m mBattery discharged (Chapter 1).
m mFuel system malfunctioning (Chapter 4).
m mInjector(s) leaking or carburettor automatic choke faulty (Chap-
ter 4).
m mDistributor rotor carbon-tracked (Chapter 5).
Engine hard to start when hot
m
mAir filter element clogged (Chapter 1).
m mFuel not reaching the fuel injection system or carburettor (Chap-
ter 4).
m mCorroded battery connections, especially earth (negative)
connection (Chapter 1).
Starter motor noisy or excessively-rough in
engagement
m mPinion or flywheel gear teeth worn or broken (Chapter 5).
m mStarter motor mounting bolts loose or missing (Chapter 5).
Engine starts, but stops immediately
m
mLoose or faulty electrical connections at distributor, coil or
alternator (Chapter 5).
m mInsufficient fuel reaching the fuel injector(s) or carburettor
(Chapters 1 and 4).
m mDamaged fuel injection system speed sensors (Chapter 5).
m mFaulty fuel injection relays (Chapter 5).
Oil puddle under engine
m
mOil sump gasket and/or sump drain plug seal leaking (Chapter 2).
m mOil pressure sender unit leaking (Chapter 2).
m mValve cover gaskets leaking (Chapter 2).
m mEngine oil seals leaking (Chapter 2).
Engine idles erratically
m
mVacuum leakage (Chapter 4).
m mAir filter element clogged (Chapter 1).
m mFuel pump not delivering sufficient fuel to the fuel injection system
or carburettor (Chapter 4).
m mLeaking head gasket (Chapter 2).
m mTiming belt/chain and/or sprockets worn (Chapter 2).
m mCamshaft lobes worn (Chapter 2).
m mFaulty charcoal canister, where fitted (Chapter 6). This Section provides an easy-reference guide to the more
common problems which may occur during the operation of your
vehicle. These problems and their possible causes are grouped under
headings denoting various components or systems, such as Engine,
Cooling system, etc. They also refer you to the Chapter and/or
Section which deals with the problem.
Remember that successful fault diagnosis is not a mysterious
black art practised only by professional mechanics. It is simply the
result of the right knowledge combined with an intelligent, systematic
approach to the problem. Always work by a process of elimination,
starting with the simplest solution and working through to the mostcomplex - and never overlook the obvious. Anyone can run the fuel
tank dry or leave the lights on overnight, so don’t assume that you are
exempt from such oversights.
Finally, always establish a clear idea of why a problem has
occurred, and take steps to ensure that it doesn’t happen again. If the
electrical system fails because of a poor connection, check all other
connections in the system to make sure that they don’t fail as well. If a
particular fuse continues to blow, find out why - don’t just renew one
fuse after another. Remember, failure of a small component can often
be indicative of potential failure or incorrect functioning of a more
important component or system.
Engine

REF•11
REF
Fault Finding
Engine misses at idle speed
m mSpark plugs worn or incorrectly-gapped (Chapter 1).
m mFaulty spark plug HT leads (Chapter 1).
m mVacuum leaks (Chapter 1).
m mIncorrect ignition timing (Chapter 5).
m mUneven or low compression (Chapter 2).
m mFaulty charcoal canister, where fitted (Chapter 6).
Engine misses throughout driving speed range
m
mFuel filter clogged and/or impurities in the fuel system (Chapter 1).
m mLow fuel output at the injectors, or partially-blocked carburettor
jets (Chapter 4).
m mFaulty or incorrectly-gapped spark plugs (Chapter 1).
m mIncorrect ignition timing (Chapter 5).
m mCracked distributor cap, disconnected distributor HT leads, or
damaged distributor components (Chapter 1).
m mFaulty spark plug HT leads (Chapter 1).
m mFaulty emission system components (Chapter 6).
m mLow or uneven cylinder compression pressures (Chapter 2).
m mWeak or faulty ignition system (Chapter 5).
m mVacuum leak in fuel injection system, intake manifold or vacuum
hoses (Chapter 4).
Engine misfires on acceleration
m mSpark plugs fouled (Chapter 1).
m mFuel injection system or carburettor malfunctioning (Chapter 4).
m mFuel filter clogged (Chapters 1 and 4).
m mIncorrect ignition timing (Chapter 5).
m mIntake manifold air leak (Chapter 4).
Engine surges while holding accelerator steady
m
mIntake air leak (Chapter 4).
m mFuel pump faulty (Chapter 4).
m mLoose fuel injector harness connections (Chapters 4 and 6).
m mDefective ECU (Chapter 5).
Engine lacks power
m
mIncorrect ignition timing (Chapter 5).
m mExcessive play in distributor shaft (Chapter 5).
m mWorn rotor, distributor cap or HT leads (Chapters 1 and 5).
m mFaulty or incorrectly-gapped spark plugs (Chapter 1).
m mFuel injection system or carburettor malfunctioning (Chapter 4).
m mFaulty coil (Chapter 5).
m mBrakes binding (Chapter 1).
m mAutomatic transmission fluid level incorrect (Chapter 1).
m mClutch slipping (Chapter 8).
m mFuel filter clogged and/or impurities in the fuel system (Chapter 1).
m mEmission control system not functioning properly (Chapter 6).
m mLow or uneven cylinder compression pressures (Chapter 2).
Engine stalls
m
mIdle speed incorrect (Chapter 1).
m mFuel filter clogged and/or water and impurities in the fuel system
(Chapter 1).
m mDistributor components damp or damaged (Chapter 5).
m mFaulty emissions system components (Chapter 6).
m mFaulty or incorrectly-gapped spark plugs (Chapter 1).
m mFaulty spark plug HT leads (Chapter 1).
m mVacuum leak in the fuel injection system, intake manifold or
vacuum hoses (Chapter 4).
Engine backfires
m mEmissions system not functioning properly (Chapter 6).
m mIgnition timing incorrect (Chapter 5).
m mFaulty secondary ignition system (cracked spark plug insulator,
faulty plug HT leads, distributor cap and/or rotor) (Chapters 1 and 5).
m mFuel injection system or carburettor malfunctioning (Chapter 4).
m mVacuum leak at fuel injector(s), intake manifold or vacuum hoses
(Chapter 4).
m mValve clearances incorrect (Chapter 1), or valve(s) sticking or
damaged (Chapter 2).
Pinking or knocking engine sounds when
accelerating or driving uphill
m mIncorrect grade of fuel.
m mIgnition timing incorrect (Chapter 5).
m mFuel injection system or carburettor in need of adjustment (Chap-
ter 4).
m mDamaged spark plugs or HT leads, or incorrect type fitted (Chapter 1).
m mWorn or damaged distributor components (Chapter 5).
m mFaulty emission system (Chapter 6).
m mVacuum leak (Chapter 4).
Engine runs with oil pressure light on
Caution: Stop the engine immediately if the oil
pressure light comes on and establish the cause.
Running the engine while the oil pressure is low can
cause severe damage.
m mLow oil level (Chapter 1).
m mIdle speed too low (Chapter 1).
m mShort-circuit in wiring (Chapter 12).
m mFaulty oil pressure sender unit (Chapter 2).
m mWorn engine bearings and/or oil pump (Chapter 2).
Engine runs-on after switching off
m
mIdle speed too high (Chapter 1).
m mExcessive engine operating temperature (Chapter 3).
m mIncorrect fuel octane grade.
m mSpark plugs defective or incorrect grade (Chapter 1).
Engine electrical system
Battery will not hold charge
m
mAlternator drivebelt defective or not adjusted properly (Chapter 1).
m mElectrolyte level low (Chapter 1).
m mBattery terminals loose or corroded (Chapter 1).
m mAlternator not charging properly (Chapter 5).
m mLoose, broken or faulty wiring in the charging circuit (Chapter 5).
m mShort in vehicle wiring (Chapters 5 and 12).
m mInternally-defective battery (Chapters 1 and 5).
m mIgnition (no-charge) warning light bulb blown - on some early
models (Chapter 5)
Ignition (no-charge) warning light fails to go out
m mFaulty alternator or charging circuit (Chapter 5).
m mAlternator drivebelt defective or out of adjustment (Chapter 1).
m mAlternator voltage regulator inoperative (Chapter 5).
Ignition (no-charge) warning light fails to come on
when key is turned
m mWarning light bulb defective (Chapter 12).
m mFault in the printed circuit, wiring or bulbholder (Chapter 12).

REF•12Fault Finding
Fuel system
Excessive fuel consumption
m mDirty or clogged air filter element (Chapter 1).
m mIgnition timing incorrect (Chapter 5).
m mEmissions system not functioning properly (Chapter 6).
m mFuel injection internal parts or carburettor jets excessively worn or
damaged (Chapter 4).
m mLow tyre pressure or incorrect tyre size (Chapter 1).
m mUnsympathetic driving style, or unfavourable conditions.
Fuel leakage and/or fuel odour
Warning: Don’t drive the vehicle if a fuel leak is
suspected. Leaking fuel in the engine compartment
could catch fire.
m mLeak in a fuel feed or vent line (Chapter 4).
m mTank overfilled.
m mFuel injector or carburettor parts excessively worn, or fuel system
gaskets leaking (Chapter 4).
Cooling system
Overheating
m mInsufficient coolant in system (Chapter 1).
m mWater pump drivebelt defective or out of adjustment (Chapter 1).
m mRadiator matrix blocked, or grille restricted (Chapter 3).
m mThermostat faulty (Chapter 3).
m mRadiator cap not maintaining proper pressure (Chapter 3).
m mIgnition timing incorrect (Chapter 5).
Overcooling
m
mFaulty thermostat (Chapter 3).
External coolant leakage
m
mDeteriorated/damaged hoses; loose clamps (Chapters 1 and 3).
m mWater pump seal defective (Chapters 1 and 3).
m mLeakage from radiator matrix, heater matrix or header tank
(Chapter 3).
m mRadiator/engine block drain plugs or water jacket core plugs
leaking (Chapters 2 and 3).
Internal coolant leakage
m mLeaking cylinder head gasket (Chapter 2).
m mCracked cylinder bore or cylinder head (Chapter 2).
Coolant loss
m
mToo much coolant in system (Chapter 1).
m mCoolant boiling away because of overheating (see above).
m mInternal or external leakage (see above).
m mFaulty radiator cap (Chapter 3).
Poor coolant circulation
m
mInoperative water pump (Chapter 3).
m mRestriction in cooling system (Chapters 1 and 3).
m mWater pump drivebelt defective/out of adjustment (Chapter 1).
m mThermostat sticking (Chapter 3).
Clutch
Pedal travels to floor - no pressure or very little
resistance
m mMaster or slave cylinder faulty (Chapter 8).
m mFluid line burst or leaking (Chapter 8).
m mConnections leaking (Chapter 8).
m mNo fluid in reservoir (Chapter 1).
m mIf fluid is present in master cylinder dust cover, master cylinder rear
seal has failed (Chapter 8).
m mBroken release bearing or fork (Chapter 8).
Fluid in area of master cylinder dust cover, and on
pedal
m mRear seal failure in master cylinder (Chapter 8).
Fluid on slave cylinder
m
mSlave cylinder plunger seal faulty (Chapter 8).
Pedal feels “spongy” when depressed
m
mAir in system (Chapter 8).
Unable to select gears
m
mFaulty transmission (Chapter 7).
m mFaulty clutch plate (Chapter 8).
m mFork and bearing not assembled properly (Chapter 8).
m mFaulty pressure plate (Chapter 8).
m mPressure plate-to-flywheel bolts loose (Chapter 8).
Clutch slips (engine speed increases with no
increase in vehicle speed)
m mClutch plate worn (Chapter 8).
m mClutch plate is oil-soaked by leaking rear main seal (Chapter 8).
m mWarped pressure plate or flywheel (Chapter 8).
m mWeak diaphragm spring (Chapter 8).
m mClutch plate overheated.
Grabbing (chattering) as clutch is engaged
m
mOil on clutch plate lining, burned or glazed facings (Chapter 8).
m mWorn or loose engine or transmission mountings (Chapters 2
and 7A).
m mWorn splines on clutch plate hub (Chapter 8).
m mWarped pressure plate or flywheel (Chapter 8).
Noise in clutch area
m
mFork improperly fitted (Chapter 8).
m mFaulty release bearing (Chapter 8).
Clutch pedal stays on floor
m
mFork binding in housing (Chapter 8).
m mBroken release bearing or fork (Chapter 8).
High pedal effort
m
mFork binding in housing (Chapter 8).
m mPressure plate faulty (Chapter 8).
m mIncorrect-size master or slave cylinder fitted (Chapter 8).