1987 BMW 3 SERIES handbrake

the stop-light switch (see Section 13). Note:
On right-hand-drive models, the brake pedal
in on the right-hand side of the vehicle, and is
connected to the left-hand side by a cross-
shaft. The adjustment is carried out on the
pushrod at the left-hand side, but the
dimension is measured at the pedal on the
right-hand side.
14On 5-Series models, adjust the brake
pedal height and the stop-light switch (see
Section 13).
15Refit the master cylinder (see Section 7)
and attach the vacuum hose.
16Carefully test the operation of the brakes
before returning the vehicle to normal use
9 Hydraulic brake servo-
description, removal and
refitting
3
Warning: Brake fluid is
poisonous. It is also an effective
paint stripper. Refer to the
warning at the start of Section 16.
Description
1On 5-Series E28 (“old-shape”) models, a
hydraulic brake servo system is fitted. The
servo unit, located between the brake pedal
(left-hand-drive) or cross-shaft lever (right-
hand-drive) and the master cylinder, is
operated by hydraulic pressure generated by
the power steering pump. When the engine is
running, the power steering pump supplies
hydraulic pressure to a power flow regulator/
accumulator. The regulator/accumulator
stores and regulates the pressure to the
hydraulic brake servo. When you press the
brake pedal, the pressure in the servo helps
actuate the master cylinder, reducing pedal
effort.
2The hydraulic brake servo cannot be
overhauled; if it fails, a new one must be fitted.
Testing the system requires special tools, so
even fault diagnosis is beyond the scope of
the home mechanic. If the system fails, take it
to a dealer service department or other
qualified garage for repairs.
Removal and refitting
3With the engine off, discharge the hydraulic
accumulator by depressing the brake pedal
20 times or more.
4Remove the master cylinder (see Section 7).
5Clean the area around the return and
supply line fittings, then disconnect them.
Plug the lines, to prevent dirt from entering the
system, and to prevent further fluid loss.
Caution: Even a particle of dirt
can damage the servo, so be
extremely careful to prevent dirt
from entering the system while
the lines are disconnected.
6Working from inside the passenger
compartment, remove the lower left trim
panels above the brake pedal (left-hand-drive
models) or glovebox and trim (right-hand-drive models). On left-hand-drive models, also
disconnect the pedal return spring.
7Prise off the retaining clip, and disconnect
the pushrod from the brake pedal (see
illustration 8.9) or cross-shaft lever.
8Remove the four mounting nuts and
remove the brake servo (see illus-
tration 8.10).
9Refitting is the reverse of removal. Tighten
the hydraulic lines to the torque listed in this
Chapter’s Specifications. Note:Don’t try to
tighten these fittings without a torque wrench.
If they’re loose, they can leak, which can affect
system operation; if they’re tight, they can be
damaged, and they’ll also leak. You’ll need a
crowfoot-type split ring (“brake”) attachment
for your torque wrench to tighten the fittings
properly.
10When you’re done, bleed the brake
hydraulic system (Section 16) and adjust the
brake pedal travel and the stop-light switch
(see Section 13).
10 Handbrake cable(s)- renewal
2
1Peel back the boot at the base of the
handbrake lever, and remove the handbrake
cable adjusting nut (see illustration)which
also secures the cable to the handbrake lever.There are two cables - one for each rear wheel
- and a nut for each cable. On some models, it
may be necessary to remove the centre
console completely for access.
2Raise the vehicle and support it securely on
axle stands.
3Remove the rear brake drum (see Section 6)
or rear brake disc (see Section 5).
4On rear drum models, unhook the
handbrake cable from the lever on the rear
brake shoe (see Section 6). On rear disc
models, remove the handbrake shoes and the
actuator (see Section 12) and unhook the
handbrake cable from the actuator (see
illustrations).
5On rear drum models, pull the cable and
cable conduit (tube) out of the back of the
brake backplate, then detach the cable
conduit from the cable clips on the back of
the trailing arm (it’s easier to pull out the old
cable, and fit the new cable, with the conduit
straight instead of curved). On rear disc
models, it’s unnecessary to detach the cable
conduit from the brake backplate, but it’s a
good idea to detach the conduit from the clips
and guides securing it to the trailing arm, to
take some of the bend out of the conduit.
6Working from the wheel end of the cable
conduit, pull the cable out of the conduit (see
illustration).
7Lubricate the new cable with multi-purpose
grease, then insert it into the cable conduit
Braking system 9•11
10.1 Peel back the handbrake lever boot
and remove the relevant handbrake cable
adjusting nut (both arrowed)
10.6 Pull the cable out of its conduit;
before you refit the new cable, be sure to
lubricate it with multi-purpose grease10.4b . . . then remove the pin securing the
cable to the inner cam, and remove the
inner cam
10.4a To detach the handbrake cable from
the handbrake actuator on models with rear
disc brakes, pull on the outer cam and
disconnect it from the inner cam . . .
9

and push it through until the forward end
comes out at the handbrake lever.
8Insert the cable conduit through the
backplate, and attach the rear end of the
cable to the handbrake lever (rear drum
models) or the actuator (rear disc models).
Make sure you don’t kink the cable while
connecting it.
9Refit the cable conduit to the clips on the
back of the trailing arm.
10On rear drum models, refit the brake
shoes and drum (see Section 6). On rear disc
models, refit the handbrake shoes and
actuator (see Section 12) and the rear brake
disc (see Section 5).
11Lower the vehicle, and refit the adjusting
nut at the handbrake lever. Adjust the
handbrake cable (see Section 11) and refit the
handbrake lever boot.
11 Handbrake- adjustment
2
Rear drum brake models
Note:Adjustment of the handbrake cable(s)
on models with rear drum brakes should only
be necessary when you renew a cable or
detach if from the rear brake assembly for
some reason. Failure of the handbrake system
to hold the vehicle usually indicates worn
brake shoes or a faulty self-adjusting
mechanism.
1Raise the rear of the vehicle, and place it
securely on axle stands.
2Fully release the handbrake lever, then
apply the brakes firmly several times with the
footbrake pedal.
3Pull the handbrake lever up five clicks.
4Tighten or loosen the adjusting nuts by
equal amounts until the rear brake shoes just
begin to drag on the brake drum. You should
feel the same amount of resistance at both
wheels when you rotate them.
5Release the handbrake lever, and verify that
the wheels rotate freely. If they don’t, re-
adjust them.
Rear disc brake models
Note: The handbrake system is not self-
adjusting on models with rear disc brakes. The
handbrake therefore requires periodic
adjustment to compensate for wear. It should
also be adjusted anytime either cable, brake
disc or handbrake assembly is renewed or
removed for some reason.
6Slowly apply the handbrake, and count the
number of clicks at the lever. If the lever can
be pulled up further than the eighth click,
adjust the handbrake cable as follows.
7Peel back the handbrake lever boot, and
loosen the cable adjusting nut (see
illustration 10.1). On some models, it may be
necessary to remove the centre console
completely for access.
8Loosen a single bolt in each rear wheel.Raise the vehicle and place it securely on axle
stands.
9Remove the bolt you loosened in each rear
wheel. Turn the wheel until, using a torch, you
can see the adjuster starwheel through the
bolt hole.
10Turn the adjuster - clockwise to expand
the shoes, anti-clockwise to retract them -
until the brake shoes just contact the brake
drum (see illustration 5.6d). Back off the
brake shoes so the wheel spins freely (three to
four teeth on the adjuster). Note:If the
adjuster starwheel is hard to turn, remove the
wheel and brake disc, lubricate the adjuster
wheel, and try again.
11With the disc fitted, apply the handbrake
three times to stretch and seat the cables,
then slowly pull up on the handbrake lever to
the fifth click. Tighten the cable adjusting nuts
by equal amounts until the rear brake shoes
just touch the brake drum. Verify that both
wheels have the same amount of resistance.
12Release the handbrake, and verify that
both rear wheels rotate freely.
13Tighten the wheel bolts to the torque
listed in Chapter 1 Specifications.
12 Handbrake assembly-
check, removal and refitting
2
Warning: The handbrake linings
on rear disc brake models may
be manufactured of asbestos-
based material. Refer to the
warning at the start of Section 6. When
servicing these components, do not create
dust by grinding or sanding the linings.
1The handbrake system should be checked
regularly. With the vehicle parked on a hill,
apply the handbrake, select neutral, and
check that the handbrake alone will hold the
vehicle when the footbrake is released (be
sure to stay in the vehicle during this check).
However, every 2 years (or whenever a fault is
suspected), the assembly itself should be
inspected.
2With the vehicle raised and supported onaxle stands, remove the rear wheels.
3On rear brake drum models, refer to
Chapter 1; checking the thickness of the
brake shoes is a routine maintenance
procedure.
4On rear disc brake models, remove the rear
discs as outlined in Section 5. Support the
caliper assemblies with a coat hanger or
heavy wire; do not disconnect the brake line
from the caliper.
5With the disc removed, the handbrake
components are visible, and can be inspected
for wear and damage. The linings should last
the life of the vehicle. However, they can wear
down if the handbrake system has been
improperly adjusted, or if the handbrake is
regularly used to stop the vehicle. There is no
minimum thickness specification for the
handbrake shoes, but as a rule of thumb, if
the shoe material is less than 1.5 mm thick,
you should renew them. Also check the
springs and adjuster mechanism and inspect
the drum for deep scratches and other
damage.
Removal and refitting
Note:The following procedure applies only to
models with rear disc brakes. The handbrake
system on models with rear drum brakes is an
integral part of the rear brake assembly (see
Section 6).
6Loosen the rear wheel bolts, raise the rear
of the vehicle and place it securely on axle
stands. Remove the rear wheels. Remove the
brake discs (see Section 5). Work on only one
side at a time, so you can use the other side
as a reference during reassembly, and to
avoid mixing up parts.
7Remove the shoe return and hold-down
springs (see illustrations).
8Remove the shoes (see illustration).
9Refitting is the reverse of removal. When
you’re done, the actuator should be properly
seated between the two shoes as shown (see
illustration).
10After refitting the brake disc, adjust the
handbrake shoes. Temporarily refit two wheel
bolts, turn the adjuster (see illustration 5.6d)
and expand the shoes until the disc locks,
9•12 Braking system
12.7b Remove the upper shoe
return spring12.7a Remove the lower shoe return
spring (diagonal cutting pliers are being
used here because they grip the spring
well, but care must be taken not to cut or
nick the spring)

4Inspect and, if necessary, renew any worn
or defective bolts, washers, bushes or links.
Refitting
5Refitting is the reverse of removal. Tighten
all fasteners securely.
13 Rear trailing arms (3-Series)
- removal and refitting
3
Removal
1Loosen the wheel bolts, then chock the
front wheels. Raise the rear of the vehicle, and
support it securely on axle stands. Remove
the wheel(s).
2Remove the driveshaft (see Chapter 8), or
disconnect it from the final drive output
flange.
3Disconnect the rear brake hose from the
metal brake line at the bracket on the trailing
arm (see illustration). Note: For information
on disconnecting brake hose-to-metal line
connections, see Chapter 9. Plug the line and
hose, to prevent dirt ingress and loss of brake
fluid.
4Disconnect the handbrake cable (see
Chapter 9).
5Disconnect the lower end of the shockabsorber from the trailing arm (see Section 9),
and lower the trailing arm.
6Remove the trailing arm pivot bolts (see
illustration)and remove the trailing arm.
7Inspect the pivot bolt bushes. If they’re
cracked, dried out or torn, take the trailing
arm to an engineering works and have them
new ones fitted. Each bush has a larger
diameter shoulder on one end. Make sure this
larger diameter shoulder on each bush faces
away from the trailing arm, ie the inner bush
shoulder faces the centre of the vehicle, and
the outer bush shoulder faces away from the
vehicle.Refitting
8Refitting is the reverse of removal. Support
the trailing arm with a trolley jack, and raise it
to simulate normal ride height, then tighten
the nuts and bolts to the torque listed in this
Chapter’s Specifications. Be sure to bleed the
brakes as described in Chapter 9.
14 Rear trailing arms (5-Series)
- removal and refitting
3
Removal
1Loosen the wheel bolts, then chock the
front wheels. Raise the rear of the vehicle and
support it securely on axle stands. Remove
the wheel(s).2Remove the driveshaft (see Chapter 8).
3Disconnect the rear brake hose from the
metal brake line at the bracket on the trailing
arm (see illustration). Note: For information
on disconnecting brake hose-to-metal line
connections, see Chapter 9. Plug the line and
hose, to prevent dirt ingress and loss of brake
fluid.
4Disconnect the handbrake cable from the
handbrake actuator, and unclip the handbrake
cable from the trailing arm (see Chapter 9).
5Remove the ABS wheel sensor (if
applicable) from the trailing arm, and unclip
the sensor wire harness from the arm.
Position the sensor aside so it won’t be
damaged during removal of the trailing arm.
6If you’re removing the right trailing arm,
unplug the connector for the brake pad wear
sensor, if applicable.
7Disconnect the rear anti-roll bar from the
trailing arm (see Section 12).
8On 1983 and later models, remove one of
the rear axle carrier bolts (see illustration).
9Disconnect the shock absorber lower
mounting bolt (see Section 11).
10Remove the two trailing arm pivot bolts
and nuts, and remove the trailing arm from the
vehicle.
11Inspect the pivot bolt bushes. If they’re
cracked, dried out or torn, take the trailing
arm to an engineering works, and have new
ones fitted. The bush inner sleeve is longer on
one side. Make sure the bushes are fitted with
10•10 Suspension and steering systems
14.3 Disconnect the brake hose (left
arrow) from the fitting on the metal brake
line (right arrow) at this bracket13.6 Nut (arrowed) for the outer pivot bolt
13.3 Disconnect the rear brake hose
(middle arrow) from the metal brake line
fitting (right arrow) at this bracket on the
trailing arm, then plug the line and hose
immediately; the other arrow points to the
nut for the inner pivot bolt
12.3b Bolt (arrowed) connecting rear anti-
roll bar link to trailing arm (5-Series)12.3a A nut and bolt (arrowed) connect
each rear anti-roll bar link to the rear
trailing arms (3-Series)12.2 Rear anti-roll bar bracket bolt
(arrowed) (3-Series)

REF•1
REF
MOT Test Checks
This is a guide to getting your vehicle through the MOT test.
Obviously it will not be possible to examine the vehicle to the same
standard as the professional MOT tester. However, working through
the following checks will enable you to identify any problem areas
before submitting the vehicle for the test.
Where a testable component is in borderline condition, the tester
has discretion in deciding whether to pass or fail it. The basis of such
discretion is whether the tester would be happy for a close relative or
friend to use the vehicle with the component in that condition. If the
vehicle presented is clean and evidently well cared for, the tester may
be more inclined to pass a borderline component than if the vehicle is
scruffy and apparently neglected.
It has only been possible to summarise the test requirements here,
based on the regulations in force at the time of printing. Test standards
are becoming increasingly stringent, although there are some
exemptions for older vehicles. For full details obtain a copy of the Haynes
publication Pass the MOT! (available from stockists of Haynes manuals).
An assistant will be needed to help carry out some of these checks.
The checks have been sub-divided into four categories, as follows:
HandbrakeMTest the operation of the handbrake.
Excessive travel (too many clicks) indicates
incorrect brake or cable adjustment.
MCheck that the handbrake cannot be
released by tapping the lever sideways. Check
the security of the lever mountings.
Footbrake
MDepress the brake pedal and check that it
does not creep down to the floor, indicating a
master cylinder fault. Release the pedal, wait
a few seconds, then depress it again. If the
pedal travels nearly to the floor before firm
resistance is felt, brake adjustment or repair is
necessary. If the pedal feels spongy, there is
air in the hydraulic system which must be
removed by bleeding.MCheck that the brake pedal is secure and in
good condition. Check also for signs of fluid
leaks on the pedal, floor or carpets, which
would indicate failed seals in the brake master
cylinder.
MCheck the servo unit (when applicable) by
operating the brake pedal several times, then
keeping the pedal depressed and starting the
engine. As the engine starts, the pedal will
move down slightly. If not, the vacuum hose or
the servo itself may be faulty.
Steering wheel and column
MExamine the steering wheel for fractures or
looseness of the hub, spokes or rim.
MMove the steering wheel from side to side
and then up and down. Check that the
steering wheel is not loose on the column,
indicating wear or a loose retaining nut.
Continue moving the steering wheel as before,
but also turn it slightly from left to right.
MCheck that the steering wheel is not loose
on the column, and that there is no abnormalmovement of the steering wheel, indicating
wear in the column support bearings or
couplings.
Windscreen and mirrors
MThe windscreen must be free of cracks or
other significant damage within the driver’s
field of view. (Small stone chips are
acceptable.) Rear view mirrors must be
secure, intact, and capable of being adjusted.
1Checks carried out
FROM THE DRIVER’S SEAT
1Checks carried out
FROM THE DRIVER’S
SEAT2Checks carried out
WITH THE VEHICLE
ON THE GROUND3Checks carried out
WITH THE VEHICLE
RAISED AND THE
WHEELS FREE TO
TURN4Checks carried out on
YOUR VEHICLE’S
EXHAUST EMISSION
SYSTEM

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•14Fault Finding
Brakes
Note:Before assuming that a brake problem exists, make sure that:
a) The tyres are in good condition and properly inflated (Chapter 1).
b) The wheel alignment (tracking) is correct (Chapter 10).
c) The vehicle is not loaded with weight in an unequal manner.
Vehicle pulls to one side during braking
m mIncorrect tyre pressures (Chapter 1).
m mWheel alignment (tracking) incorrect (Chapter 10)
m mUnmatched tyres on same axle.
m mRestricted brake lines or hoses (Chapter 9).
m mMalfunctioning caliper assembly (Chapter 9).
m mLoose suspension parts (Chapter 10).
m mLoose calipers (Chapter 9).
Noise (high-pitched squeal) when the brakes are
applied
m mFront and/or rear disc brake pads worn out. The noise comes from
the wear sensor rubbing against the disc. Renew the pads
immediately (Chapter 9).
Brake vibration (pedal pulsates)
Note:If the vehicle has ABS, it is normal for the brake pedal to pulsate
when the system is working.
m mExcessive lateral disc run-out (Chapter 9).
m mParallelism not within specifications (Chapter 9).
m mUneven pad wear - caused by caliper not sliding, due to improper
clearance or dirt (Chapter 9).
m mDefective disc (Chapter 9).
Excessive brake pedal travel
m
mPartial brake system failure (Chapter 9).
m mInsufficient fluid in master cylinder (Chapters 1 and 9).
m mAir trapped in system (Chapters 1 and 9).
Excessive pedal effort required to stop vehicle
m
mMalfunctioning brake servo unit (Chapter 9).
m mPartial system failure (Chapter 9).
m mExcessively-worn pads or shoes (Chapter 9).
m mCaliper piston stuck or sluggish (Chapter 9).
m mBrake pads contaminated with oil or grease (Chapter 9).
m mNew pads fitted and not yet seated. It will take a while for the new
material to seat against the disc.
Dragging brakes
m mMaster cylinder pistons not returning correctly (Chapter 9).
m mRestricted brakes lines or hoses (Chapters 1 and 9).
m mIncorrect handbrake adjustment (Chapter 9).
m mRear drum brake self-adjuster mechanism faulty (when applicable)
(Chapter 9).
Grabbing or uneven braking action
m mMalfunction of brake servo unit (Chapter 9).
m mBinding brake pedal mechanism (Chapter 9).
Brake pedal feels “spongy” when depressed
m
mAir in hydraulic lines (Chapter 9).
m mMaster cylinder mounting bolts loose (Chapter 9).
m mMaster cylinder defective (Chapter 9).
Brake pedal travels to the floor with little resistance
m
mLittle or no fluid in the master cylinder reservoir, caused by leaking
caliper piston(s), loose, damaged or disconnected brake lines
(Chapter 9).
Handbrake does not hold
m mHandbrake linkage incorrectly adjusted (Chapter 9).
m mHandbrake shoe linings worn out or contaminated (Chapter 9).

REF•22Glossary of Technical Terms
EEGR valveA valve used to introduce exhaust
gases into the intake air stream.
Electronic control unit (ECU)A computer
which controls (for instance) ignition and fuel
injection systems, or an anti-lock braking
system. For more information refer to the
Haynes Automotive Electrical and Electronic
Systems Manual.
Electronic Fuel Injection (EFI)A computer
controlled fuel system that distributes fuel
through an injector located in each intake port
of the engine.
Emergency brakeA braking system,
independent of the main hydraulic system,
that can be used to slow or stop the vehicle if
the primary brakes fail, or to hold the vehicle
stationary even though the brake pedal isn’t
depressed. It usually consists of a hand lever
that actuates either front or rear brakes
mechanically through a series of cables and
linkages. Also known as a handbrake or
parking brake.
EndfloatThe amount of lengthwise
movement between two parts. As applied to a
crankshaft, the distance that the crankshaft
can move forward and back in the cylinder
block.
Engine management system (EMS)A
computer controlled system which manages
the fuel injection and the ignition systems in
an integrated fashion.
Exhaust manifoldA part with several
passages through which exhaust gases leave
the engine combustion chambers and enter
the exhaust pipe.
FFan clutchA viscous (fluid) drive coupling
device which permits variable engine fan
speeds in relation to engine speeds.Feeler bladeA thin strip or blade of hardened
steel, ground to an exact thickness, used to
check or measure clearances between parts.
Firing orderThe order in which the engine
cylinders fire, or deliver their power strokes,
beginning with the number one cylinder.
Flywheel A heavy spinning wheel in which
energy is absorbed and stored by means of
momentum. On cars, the flywheel is attached
to the crankshaft to smooth out firing
impulses.
Free playThe amount of travel before any
action takes place. The “looseness” in a
linkage, or an assembly of parts, between the
initial application of force and actual
movement. For example, the distance the
brake pedal moves before the pistons in the
master cylinder are actuated.
FuseAn electrical device which protects a
circuit against accidental overload. The typical
fuse contains a soft piece of metal which is
calibrated to melt at a predetermined current
flow (expressed as amps) and break the
circuit.
Fusible linkA circuit protection device
consisting of a conductor surrounded by
heat-resistant insulation. The conductor is
smaller than the wire it protects, so it acts as
the weakest link in the circuit. Unlike a blown
fuse, a failed fusible link must frequently be
cut from the wire for replacement.
GGapThe distance the spark must travel in
jumping from the centre electrode to the sideelectrode in a spark plug. Also refers to the
spacing between the points in a contact
breaker assembly in a conventional points-
type ignition, or to the distance between the
reluctor or rotor and the pickup coil in an
electronic ignition.
GasketAny thin, soft material - usually cork,
cardboard, asbestos or soft metal - installed
between two metal surfaces to ensure a good
seal. For instance, the cylinder head gasket
seals the joint between the block and the
cylinder head.
GaugeAn instrument panel display used to
monitor engine conditions. A gauge with a
movable pointer on a dial or a fixed scale is an
analogue gauge. A gauge with a numerical
readout is called a digital gauge.
HHalfshaftA rotating shaft that transmits
power from the final drive unit to a drive
wheel, usually when referring to a live rear
axle.
Harmonic balancerA device designed to
reduce torsion or twisting vibration in the
crankshaft. May be incorporated in the
crankshaft pulley. Also known as a vibration
damper.
HoneAn abrasive tool for correcting small
irregularities or differences in diameter in an
engine cylinder, brake cylinder, etc.
Hydraulic tappetA tappet that utilises
hydraulic pressure from the engine’s
lubrication system to maintain zero clearance
(constant contact with both camshaft and
valve stem). Automatically adjusts to variation
in valve stem length. Hydraulic tappets also
reduce valve noise.
IIgnition timingThe moment at which the
spark plug fires, usually expressed in the
number of crankshaft degrees before the
piston reaches the top of its stroke.
Inlet manifoldA tube or housing with
passages through which flows the air-fuel
mixture (carburettor vehicles and vehicles with
throttle body injection) or air only (port fuel-
injected vehicles) to the port openings in the
cylinder head.
Exhaust manifold
Feeler blade
Adjusting spark plug gap
Gasket
EGR valve