check engine FORD MONDEO 1993 Service Repair Manual

(where fitted) and renew it if it is damaged or
worn. Apply a smear of anti-seize compound
to the sensor’s threads, to prevent them from
welding themselves to the downpipe in
service. Refit the sensor, tightening it to its
specified torque wrench setting; a slotted
socket will be required to do this (see
illustration). Reconnect the wiring and refit
the connector plug.
General description
1This system is fitted to minimise the escape
of unburned hydrocarbons into the
atmosphere. The fuel tank filler cap is sealed,
and a charcoal canister is mounted
underneath the tank, to collect and store
petrol vapours generated in the tank when the
vehicle is parked. When the engine is running,
the vapours are cleared from the canister
(under the control of the ECU via the canister-
purge solenoid valve) into the inlet tract, to be
burned by the engine during normal
combustion - see illustration 2.1A.
2To ensure that the engine runs correctly
when it is cold and/or idling, and to protect
the catalytic converter from the effects of an
over-rich mixture, the canister-purge solenoid
valve is not opened by the ECU until the
engine is fully warmed-up and running under
part-load; the solenoid valve is then switched
on and off, to allow the stored vapour to pass
into the inlet.
Checking
3Poor idle, stalling and poor driveability can
be caused by an inoperative canister-purge
solenoid valve, a damaged canister, split or
cracked hoses, or hoses connected to the
wrong fittings. Check the fuel filler cap for a
damaged or deformed gasket.
4Fuel loss or fuel odour can be caused by
liquid fuel leaking from fuel lines, a cracked or
damaged canister, an inoperative canister-purge solenoid valve, and disconnected,
misrouted, kinked or damaged vapour or
control hoses.
5Inspect each hose attached to the canister
for kinks, leaks and cracks along its entire
length. Repair or renew as necessary.
6Inspect the canister. If it is cracked or
damaged, renew it. Look for fuel leaking from
the bottom of the canister. If fuel is leaking,
renew the canister, and check the hoses and
hose routing.
7If the canister-purge solenoid valve is
thought to be faulty, unplug its electrical
connector and disconnect its vacuum hoses.
Connect a battery directly across the valve
terminals. Check that air can flow through the
valve passages when the solenoid is thus
energised, and that nothing can pass when the
solenoid is not energised. Alternatively,
connect an ohmmeter to measure the
resistance across the solenoid terminals, and
compare this reading to the one listed in the
Specifications Section at the beginning of this
Chapter. Renew the solenoid valve if it is faulty.
8Further testing should be left to a dealer
service department.
Component renewal
Charcoal canister-purge solenoid
valve
9If better access is required, remove the
plenum chamber (see Chapter 4). Disconnect
the battery negative (earth) lead - see Sec-
tion 1 of Chapter 5.10Unplug the valve’s electrical connector
(see illustration). Unclip the valve from the
bulkhead, then disconnect its vacuum hoses
and withdraw it.
11Refitting is the reverse of the removal
procedure.
Charcoal canister - Saloon and
Hatchback models
Note:Read through this procedure carefully
before starting work, and ensure that the
equipment is available that is required to carry
it out safely and with minimum risk of damage,
and to align the crossmember with sufficient
accuracy on reassembly.
12Remove the fuel tank (see Chapter 4).
13Ensure that the rear of the vehicle’s body
is supported securely on axle stands, then
support the rear suspension crossmember
with a jack. Remove the roadwheels and
unscrew the rear suspension strut top
mounting bolts (two per side - see Chapter
10).
14Use white paint or similar (do not use a
sharp-pointed scriber, which might break the
underbody protective coating and cause
rusting) to mark the exact relationship of the
crossmember to the underbody. Unscrew the
four mounting bolts (see illustration). Lower
the crossmember approximately 3 inches (75
mm) on the jack, and support it securely.
Warning: DO NOT place any part
of your body under the vehicle
when it is supported only by a
jack!
5 EVAPorative emissions control
(EVAP) system -
general information, checking
and component renewal
6•14 Emissions control systems
4.64 . . . slotted socket will be required to
tighten sensor with a torque wrench5.10 Charcoal canister-purge solenoid
valve (arrowed) is clipped to bulkhead
behind engine5.14 Support rear suspension
crossmember on jack, and remove
mounting bolts (arrowed) . . .
5.15 . . . lower crossmember by 3 inches,
and unscrew charcoal canister assembly
rear retaining bolts (arrowed) . . .5.16 . . . unplug hoses (arrowed) from
canister assembly . . .
procarmanuals.com

15Unscrew the two rearmost canister
assembly retaining bolts (see illustration).
16Unplug the two hoses from the canister
assembly, noting which way round they are
fitted (see illustration).
17Unscrew the canister assembly’s front
retaining bolt (see illustration). Withdraw the
canister assembly.
18Release the clip, and drive out the pin to
separate the canister from its bracket (see
illustration).
19On reassembly, refit the canister to its
bracket and refit the assembly to the vehicle,
tightening the retaining bolts securely, and
ensuring that the two hoses are securely
reconnected to their original unions.
20Offer up the crossmember and refit the
crossmember bolts, tightening them only
lightly at this stage.
21The crossmember must now be aligned
on the underbody. Ford specify the use of
service tool 15-097, which is a pair of tapered
guides, with attachments to hold them in the
crossmember as it is refitted (see
illustration). However, since the working
diameter of these tools is 20.4 mm, and since
the corresponding aligning holes in the
crossmember and underbody are 21 mm and
22 mm in diameter, there is a significant in-
built tolerance possible in the crossmember’s
alignment, even if the correct tools are used. If
these tools are not available, align the
crossmember by eye, centring thecrossmember aligning holes on those of the
underbody, and using the marks made on
removal for assistance. Alternatively, use a
tapered drift such as a clutch-aligning tool, or
a deep socket spanner of suitable size.
22Once the crossmember is aligned as
precisely as possible, tighten its bolts to the
specified torque (see Chapter 10
Specifications) without disturbing its position
(see illustration). Recheck the alignment
once all the bolts are securely tightened.
23The remainder of the refitting procedure is
the reverse of removal.
24Remember that, since the rear suspension
crossmember has been disturbed, the wheel
alignment and steering angles must be
checked fully and carefully as soon as
possible, with any necessary adjustments
being made. This operation is best carried out
by an experienced mechanic using proper
checking equipment; the vehicle should
therefore be taken to a Ford dealer or similar
for attention.
Charcoal canister - Estate models
25Disconnect the battery negative (earth)
lead - see Section 1 of Chapter 5.
26Raise the rear of the vehicle, and support
it securely on axle stands.
Warning: DO NOT place any part
of your body under the vehicle
when it is supported only by a
jack!27Disconnect the two hoses from the
canister assembly, noting which way round
they are fitted.
28Unscrew the canister assembly retaining
bolt and withdraw the assembly, unclipping it
from the front mounting.
29Remove the plastic cover, and drive out
the pin to separate the canister from its
bracket (see illustration).
30On refitting, secure the canister to its
bracket, and refit the assembly to the vehicle.
Tighten the retaining bolt securely, and ensure
that the two hoses are securely reconnected
to their original unions.
General information
1To reduce oxides of nitrogen (NOx)
emissions, some of the exhaust gases are
recirculated through the EGR valve to the inlet
manifold. This has the effect of lowering
combustion temperatures.
2The system consists of the EGR valve, the
EGR exhaust gas pressure differential sensor,
the EGR solenoid valve, the ECU, and various
sensors - see illustration 2.1A. The ECU is
programmed to produce the ideal EGR valve
lift for each operating condition.
Checking
EGR valve
3Start the engine and allow it to idle.
4Detach the vacuum hose from the EGR
valve, and attach a hand vacuum pump in its
place.
5Apply vacuum to the EGR valve. Vacuum
should remain steady, and the engine should
run poorly.
(a) If the vacuum doesn’t remain steady and
the engine doesn’t run poorly, renew the
EGR valve and recheck it.
(b) If the vacuum remains steady but the
engine doesn’t run poorly, remove the
6 Exhaust Gas Recirculation
(EGR) system-
general information, checking
and component renewal
Emissions control systems 6•15
6
5.22 . . . ensure aligned crossmember
does not move - Ford tools used here -
while mounting bolts are tightened5.29 Charcoal canister assembly - Estate
models - showing plastic cover (arrowed)
and pin securing canister to mounting
bracket
5.17 . . . and remove front retaining bolt
(arrowed) to release canister assembly -
Saloon and Hatchback models5.18 Release clip and drive out pin to
separate canister from mounting bracket5.21 Refitting rear suspension crossmember
with Ford service tools (arrowed) in place to
align it with underbody . . .
procarmanuals.com

EGR valve, and check the valve and the
inlet manifold for blockage. Clean or
renew parts as necessary, and recheck.
EGR system
6Any further checking of the system requires
special tools and test equipment. Take the
vehicle to a dealer service department for
checking.
Component renewal
Note:These components will be very hot
when the engine is running. Always allow the
engine to cool down fully before starting work,
to prevent the possibility of burns.
EGR valve
7Disconnect the battery negative (earth) lead
- see Section 1 of Chapter 5.
8Remove the air mass meter and resonator -
refer to Chapter 4.
9Detach the vacuum hose, unscrew the
sleeve nut securing the EGR pipe to the valve,
remove the two valve mounting bolts, and
withdraw the valve from the inlet manifold
(see illustrations). Ensure that the end of the
pipe is not damaged or distorted as the valve
is withdrawn, and note the valve’s gasket; this
must be renewed whenever the valve is
disturbed.
10Note that the metal pipe from the valve to
the manifold itself should not be disturbed - it
is not available separately from the manifold.However, check whenever the manifold is
removed that the pipe’s end fitting is securely
fastened (see illustration).
11Check the valve for sticking and heavy
carbon deposits. If such is found, clean the
valve or renew it.
12Refitting is the reverse of the removal
procedure. Apply a smear of anti-seize
compound to the sleeve nut threads, fit a new
gasket, and tighten the valve bolts to the
specified torque wrench setting.
EGR pipe
13Disconnect the battery negative (earth)
lead - see Section 1 of Chapter 5.
14Remove the air mass meter and resonator
- refer to Chapter 4.
15Unbolt the exhaust manifold heat shield
and remove both parts, or move them aside
as required to reach the end of the EGR pipe.
Unscrew the sleeve nut securing the pipe to
the exhaust manifold (see illustration).
16Undo the two screws securing the pipe to
the ignition coil bracket, then disconnect the
two vacuum hoses - note that these are of
different sizes, to ensure that they cannot be
mixed up on reconnection. Unscrew the
sleeve nut securing the EGR pipe to the valve
(see illustration). Withdraw the pipe.
17Check the condition of both hoses, and
renew them if necessary (see Chapter 1). Note
that if the exhaust gases have been backfiring
excessively - eg, due to a blocked exhaust
system - both hoses must be renewed, andtheir connections on the pipe must be cleaned
thoroughly.
18Refitting is the reverse of the removal
procedure; ensure that the hoses are securely
connected to the correct unions. Apply a
smear of anti-seize compound to the sleeve
nut threads, tighten the nuts securely, and
tighten the two screws to their specified
torque wrench setting.
EGR exhaust gas pressure differential
sensor
19Refer to Section 4 of this Chapter.
EGR solenoid valve
Note:This component can be identified by its
larger top and its two fastening screws. Do not
confuse it with the adjacent pulse-air solenoid
valve, especially when reconnecting vacuum
hoses.
20Disconnect the battery negative (earth)
lead - see Section 1 of Chapter 5.
21Remove the air mass meter and resonator
- refer to Chapter 4. If better access is
required, remove the plenum chamber also
(see illustration).
22Releasing its wire clip, unplug the
electrical connector from the valve. Remove
the two retaining screws, and withdraw the
valve from the bulkhead mounting bracket,
then label and disconnect the two vacuum
hoses.
23Refitting is the reverse of the removal
procedure; ensure that the hoses are correctly
reconnected.
6•16 Emissions control systems
6.9A Disconnecting vacuum hose from
Exhaust Gas Recirculation (EGR) valve . . .6.9B . . . unscrew EGR pipe sleeve nut and
remove bolts (arrowed) to release valve
from inlet manifold6.10 Check end fitting of EGR pipe into
inlet manifold whenever manifold is
removed, but do not disturb
6.15 Unbolt exhaust manifold heat shield,
and unscrew sleeve nut (arrowed) securing
EGR pipe to exhaust manifold . . .6.16 . . . undo screws “A” and sleeve
nut “B”, then disconnect hoses “C” - note
different sizes - to release EGR pipe6.21 EGR solenoid valve “A” and EGR
exhaust gas pressure differential sensor
“B”, located on bulkhead mounting bracket
procarmanuals.com

General information
1This system consists of the pulse-air
solenoid valve, the pulse-air valve itself,
contained in the filter housing, and the piping
- see illustration 2.1A. It injects filtered air
directly into the exhaust ports, using the
pressure variations in the exhaust gases to
draw air through from the filter housing; air will
flow into the exhaust only when its pressure is
below atmospheric. The pulse-air valve can
allow gases to flow only one way, so there is
no risk of hot exhaust gases flowing back into
the filter.
2The system’s primary function is raise
exhaust gas temperatures on start-up, thus
reducing the amount of time taken for the
oxygen sensor and catalytic converter to
reach operating temperature. Until this
happens, the system reduces emission of
unburned hydrocarbon particles (HC) and
carbon monoxide (CO) by ensuring that a
considerable proportion of these substances
remaining in the exhaust gases after
combustion are burned up, either in the
manifold itself or in the catalytic converter.
3To ensure that the system does not upset
the smooth running of the engine under
normal driving conditions, it is linked by the
pulse-air solenoid valve to the ECU, so that it
only functions during engine warm-up, when
the oxygen sensor is not influencing the
fuel/air mixture ratio.
Checking
4Poor idle, stalling, backfiring and poor
driveability can be caused by a fault in the
system.
5Inspect the vacuum pipe/hose connected
between the filter housing and the solenoid
valve for kinks, leaks and cracks along its
entire length. Repair or renew as necessary.
6Inspect the filter housing and piping. If
either is cracked or damaged, renew it.7If the pulse-air solenoid valve is thought to
be faulty, unplug its electrical connector and
disconnect its vacuum hoses. Connect a
battery directly across the valve terminals,
and check that air can flow through the valve
passages when the solenoid is thus
energised, and that nothing can pass when
the solenoid is not energised. Alternatively,
connect an ohmmeter to measure the
resistance across the valve terminals, and
compare this reading to the one listed in the
Specifications Section at the beginning of this
Chapter. Renew the solenoid valve if it is
faulty.
8Further testing should be left to a dealer
service department.
Component renewal
Pulse-air solenoid valve
Note:This component can be identified by its
smaller top and its clip fastening. Do not
confuse it with the adjacent EGR solenoid
valve, especially when reconnecting vacuum
hoses.
9Disconnect the battery negative (earth) lead
- see Section 1 of Chapter 5.
10Remove the air mass meter and resonator
- refer to Chapter 4. If better access is
required, remove the plenum chamber also
(see illustration).
11Releasing its wire clip, unplug the
electrical connector, then use a small
screwdriver to release the clip securing the
valve to the bulkhead mounting bracket.Withdraw the valve, then label and disconnect
the two vacuum hoses.
12Refitting is the reverse of the removal
procedure; ensure that the hoses are correctly
reconnected.
Pulse-air filter housing
Note:This component, and those around it,
will be very hot when the engine is running.
Always allow the engine to cool down fully
before starting work, to prevent the possibility
of burns.
13Raise the front of the vehicle, and support
it securely on axle stands. Disconnect the
vacuum hose from the base of the filter
housing (see illustration).
14Disconnect the battery negative (earth)
lead - see Section 1 of Chapter 5.
15Unbolt the resonator support bracket
from the engine compartment front
crossmember, slacken the two clamp screws
securing the resonator to the air mass meter
and plenum chamber hoses, then swing the
resonator up clear of the thermostat housing
(see Chapter 4).
16Remove the screws securing the filter
housing to the piping, unscrew the mounting
bolt, then withdraw the housing (see
illustration).
17To dismantle the filter housing, undo the
four screws and separate the top from the
base of the housing; extract the foam filter,
and clean it in a suitable solvent (see
illustrations). If any of the housing’s
7 Pulse-air system -
general information
Emissions control systems 6•17
6
7.17A Remove four screws to release filter
housing top from base . . .7.17B . . .and withdraw foam filter for
cleaning, if required - note valve in base of
housing
7.10 Pulse-air solenoid valve (arrowed) is
located on bulkhead mounting bracket. It
can be identified by its smaller top and its
clip fastening - do not confuse it with the
adjacent EGR solenoid valve7.13 Disconnect vacuum hose from base
of pulse-air filter housing . . .7.16 . . . undo screws “A” to disconnect
piping from housing, and mounting
bolt “B” to release housing
procarmanuals.com

components are worn or damaged, the
assembly must be renewed.
18Refitting is the reverse of the removal
procedure.
Pulse-air piping
Note:This component, and those around it,
will be very hot when the engine is running.
Always allow the engine to cool down fully
before starting work, to prevent the possibility
of burns.
19Disconnect the battery negative (earth)
lead - see Section 1 of Chapter 5.
20Remove the air mass meter and resonator
- refer to Chapter 4.
21Unbolt the exhaust manifold heat shield;
unclip the coolant hose to allow the upper
part to be withdrawn. Apply penetrating oil to
the EGR pipe sleeve nut, and to the pulse-air
system sleeve nuts.
22Remove the EGR pipe (see Section 6).
23Remove the screws securing the filter
housing to the piping - see illustration 7.16.
Unscrew the four sleeve nuts securing the
pipes into the exhaust manifold, and remove
the piping as an assembly, taking care not to
distort it (see illustration).
24Carefully clean the piping, particularly its
threads and those of the manifold, removing
all traces of corrosion, which might prevent
them seating properly, causing air leaks when
the engine is restarted.
25On refitting, insert the piping carefully into
the cylinder head ports, taking care not to
bend or distort it. Apply anti-seize compound
to the threads, and tighten the retaining sleeve
nuts while holding each pipe firmly in its port;
if a suitable spanner is available, tighten the
sleeve nuts to the specified torque wrench
setting.
26The remainder of the refitting procedure is
the reverse of removal.
Pulse-air filter housing and piping
assembly
Note:These components, and those around
them, will be very hot when the engine is
running. Always allow the engine to cool down
fully before starting work, to prevent the
possibility of burns.
27Disconnect the battery negative (earth)
lead - see Chapter 5, Section 1. Unbolt theresonator support bracket from the engine
compartment front crossmember. Slacken the
two clamp screws securing the resonator to
the air mass meter and plenum chamber
hoses, then swing the resonator up clear of
the thermostat housing (see Chapter 4).
28Drain the cooling system (see Chapter 1)
and disconnect the coolant hose and the
coolant pipe/hose from the thermostat
housing.
29Unbolt the exhaust manifold heat shield.
Apply penetrating oil to the EGR pipe sleeve
nut, and to the pulse-air system sleeve nuts.
30Remove the EGR pipe (see Section 6).
31Unscrew the filter housing mounting bolt.
Unscrew the four sleeve nuts securing the
pipes into the exhaust manifold and remove
the assembly, taking care not to distort it (see
illustration).
32Clean the piping, particularly its threads
and those of the manifold, removing all tracesof corrosion, which might prevent them
seating properly, causing air leaks when the
engine is restarted.
33On refitting, insert the piping carefully into
the cylinder head ports, taking care not to
bend or distort it. Apply anti-seize compound
to the threads, and tighten the retaining sleeve
nuts while holding each pipe firmly in its port;
if a suitable spanner is available, tighten the
sleeve nuts to the specified torque wrench
setting.
34The remainder of the refitting procedure is
the reverse of removal. Refill the cooling
system (see Chapter 1). Run the engine,
check for exhaust leaks, and check the
coolant level when it is fully warmed-up.
General information
1The crankcase ventilation system main
components are the oil separator mounted on
the front (radiator) side of the cylinder
block/crankcase, and the Positive Crankcase
Ventilation (PCV) valve set in a rubber
grommet in the separator’s left-hand upper
end. The associated pipework consists of a
crankcase breather pipe and two flexible
hoses connecting the PCV valve to a union on
the left-hand end of the inlet manifold, and a
crankcase breather hose connecting the
cylinder head cover to the air cleaner
assembly (see illustration). A small foam filter
in the air cleaner prevents dirt from being
drawn directly into the engine.
8 Positive Crankcase Ventilation
(PCV) system -
general information
6•18 Emissions control systems
7.23 Removing pulse-air piping - take care
not to bend or distort it7.31 Remove mounting bolt (arrowed) to
remove complete pulse-air assembly -
again, take care not to bend or distort
piping
8.1 Positive Crankcase Ventilation system
1 Oil separator
2 Gasket
3 Positive Crankcase Ventilation (PCV) valve4 Cylinder block/crankcase opening
5 Crankcase breather pipe and flexible hoses
procarmanuals.com

2The function of these components is to
reduce the emission of unburned
hydrocarbons from the crankcase, and to
minimise the formation of oil sludge. By
ensuring that a depression is created in the
crankcase under most operating conditions,
particularly at idle, and by positively inducing
fresh air into the system, the oil vapours and
“blow-by” gases collected in the crankcase
are drawn from the crankcase, through the oil
separator, into the inlet tract, to be burned by
the engine during normal combustion.
Checking
3Checking procedures for the system
components are included in Chapter 1.
Component renewal
Cylinder head-to-air cleaner hose
4See Chapter 1.
Positive Crankcase Ventilation (PCV)
valve
5The valve is plugged into the oil separator.
Depending on the tools available, access to
the valve may be possible once the pulse-air
assembly has been removed (see Section 7).
If this is not feasible, proceed as outlined in
paragraph 6 below.
Oil separator
6Remove the exhaust manifold (see Chap-
ter 2, Part A). The Positive Crankcase
Ventilation (PCV) valve can now be unplugged
and flushed, or renewed, as required, as
described in Chapter 1.
7Unbolt the oil separator from the cylinder
block/crankcase, and withdraw it; remove and
discard the gasket.
8Flush out or renew the oil separator, as
required (see Chapter 1).
9On reassembly, fit a new gasket, and
tighten the fasteners to the torque wrench
settings given in the Specifications Section of
Chapter 2, Part B.
10The remainder of the refitting procedure is
the reverse of removal. Refill the cooling
system (see Chapter 1). Run the engine,
check for exhaust leaks, and check the
coolant level when it is fully warmed-up.
General information
1The exhaust gases of any petrol engine
(however efficient or well-tuned) consist
largely (approximately 99 %) of nitrogen (N
2),
carbon dioxide (CO
2), oxygen (O2), other inert
gases and water vapour (H
2O). The remaining
1 % is made up of the noxious materials
which are currently seen (CO
2apart) as the
major polluters of the environment: carbon
monoxide (CO), unburned hydrocarbons (HC),oxides of nitrogen (NO
x) and some solid
matter, including a small lead content.
2Left to themselves, most of these pollutants
are thought eventually to break down naturally
(CO and NO
x, for example, break down in the
upper atmosphere to release CO
2) having first
caused ground-level environmental problems.
The massive increase world-wide in the use of
motor vehicles, and the current popular
concern for the environment has caused the
introduction in most countries of legislation, in
varying degrees of severity, to combat the
problem.
3The device most commonly used to clean
up vehicle exhausts is the catalytic converter.
It is fitted into the vehicle’s exhaust system,
and uses precious metals (platinum and
palladium or rhodium) as catalysts to speed
up the reaction between the pollutants and
the oxygen in the vehicle’s exhaust gases, CO
and HC being oxidised to form H
2O and CO2and (in the three-way type of catalytic
converter) NO
xbeing reduced to N2. Note:
The catalytic converter is not a filter in the
physical sense; its function is to promote a
chemical reaction, but it is not itself affected
by that reaction.
4The converter consists of an element (or
“substrate”) of ceramic honeycomb, coated
with a combination of precious metals in such
a way as to produce a vast surface area over
which the exhaust gases must flow; the whole
being mounted in a stainless-steel box. A
simple “oxidation” (or “two-way”) catalytic
converter can deal with CO and HC only,
while a “reduction” (or “three-way”) catalytic
converter can deal with CO, HC and NO
x.
Three-way catalytic converters are further
sub-divided into “open-loop” (or
“uncontrolled”) converters which can remove
50 to 70 % of pollutants and “closed-loop”
(also known as “controlled” or “regulated”)
converters which can remove over 90 % of
pollutants.
5The catalytic converter fitted to the Mondeo
models covered in this manual is of the three-
way closed-loop type.
6The catalytic converter is a reliable and
simple device, which needs no maintenance
in itself, but there are some facts of which an
owner should be aware if the converter is to
function properly for its full service life.
(a) DO NOT use leaded petrol in a vehicle
equipped with a catalytic converter - the
lead will coat the precious metals,
reducing their converting efficiency, and
will eventually destroy the converter; it will
also affect the operation of the oxygen
sensor, requiring its renewal if lead-
fouled. Opinions vary as to how much
leaded fuel is necessary to affect the
converter’s performance, and whether it
can recover even if only unleaded petrol is
used afterwards; the best course of action
is, therefore, to assume the worst, and to
ensure that NO leaded petrol is used at
any time.
(b) Always keep the ignition and fuel systemswell-maintained in accordance with the
manufacturer’s schedule (Chapter 1) -
particularly, ensure that the air filter
element, the fuel filter and the spark plugs
are renewed at the correct intervals. If the
intake air/fuel mixture is allowed to
become too rich due to neglect, the
unburned surplus will enter and burn in
the catalytic converter, overheating the
element and eventually destroying the
converter.
(c) If the engine develops a misfire, do not
drive the vehicle at all (or at least as little
as possible) until the fault is cured - the
misfire will allow unburned fuel to enter
the converter, which will result in its
overheating, as noted above. For the
same reason, do not persist if the engine
refuses to start - either trace the problem
and cure it yourself, or have the vehicle
checked immediately by a qualified
mechanic.
(d) Avoid allowing the vehicle to run out of
petrol.
(e) DO NOT push- or tow-start the vehicle
unless no other alternative exists,
especially if the engine and exhaust are at
normal operating temperature. Starting
the engine in this way may soak the
catalytic converter in unburned fuel,
causing it to overheat when the engine
does start - see (b) above.
(f) DO NOT switch off the ignition at high
engine speeds, in particular, do not “blip”
the throttle immediately before switching
off. If the ignition is switched off at
anything above idle speed, unburned fuel
will enter the (very hot) catalytic converter,
with the possible risk of its igniting on the
element and damaging the converter.
(g) Avoid repeated successive cold starts
followed by short journeys. If the
converter is never allowed to reach its
proper working temperature, it will gather
unburned fuel, allowing some to pass into
the atmosphere and the rest to soak in
the element, causing it to overheat when
a long journey is made - see (b) above.
(h) DO NOT use fuel or engine oil additives -
these may contain substances harmful to
the catalytic converter. Similarly, DO NOT
use silicone-based sealants on any part of
the engine or fuel system, and do not use
exhaust sealants on any part of the
exhaust system upstream of the catalytic
converter. Even if the sealant itself does
not contain additives harmful to the
converter, pieces of it may break off and
foul the element, causing local
overheating.
(i) DO NOT continue to use the vehicle if the
engine burns oil to the extent of leaving a
visible trail of blue smoke. Unburned
carbon deposits will clog the converter
passages and reduce its efficiency; in
severe cases, the element will overheat.
(j) Remember that the catalytic converter
operates at very high temperatures -
9 Catalytic converter -
general information, checking
and component renewal
Emissions control systems 6•19
6
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hence the heat shields on the vehicle
underbody - and the casing will become
hot enough to ignite combustible
materials which brush against it. DO NOT,
therefore, park the vehicle in dry
undergrowth, over long grass or piles of
dead leaves.
(k) Remember that the catalytic converter is
FRAGILE. Do not strike it with tools
during servicing work, and take great care
when working on the exhaust system (see
Chapter 4). Ensure that the converter is
well clear of any jacks or other lifting gear
used to raise the vehicle. Do not drive the
vehicle over rough ground, road humps,
etc, in such a way as to “ground” the
exhaust system.
(l) In some cases, particularly when the
vehicle is new and/or is used for
stop/start driving, a sulphurous smell (like
that of rotten eggs) may be noticed fromthe exhaust. This is common to many
catalytic converter-equipped vehicles,
and seems to be due to the small amount
of sulphur found in some petrols reacting
with hydrogen in the exhaust, to produce
hydrogen sulphide (H
2S) gas; while this
gas is toxic, it is not produced in sufficient
amounts to be a problem. Once the
vehicle has covered a few thousand miles,
the problem should disappear - in the
meanwhile, a change of driving style, or of
the brand of petrol used, may effect a
solution.
(m) The catalytic converter on a well-
maintained and well-driven vehicle should
last for between 50 000 and 100 000
miles. From this point on, careful checks
should be made at regular intervals to
ensure that the converter is still operating
efficiently. If the converter is no longer
effective, it must be renewed.
Checking
7Checking the operation of a catalytic
converter requires expensive and
sophisticated diagnostic equipment, starting
with a high-quality exhaust gas analyser. If the
level of CO in the exhaust gases is too high, a
full check of the engine management system
must be carried out (see Section 3 of this
Chapter) to eliminate all other possibilities
before the converter is suspected of being
faulty.
8The vehicle should be taken to a Ford
dealer for this work to be carried out using the
correct diagnostic equipment; do not waste
time trying to test the system without such
facilities.
Component renewal
9The catalytic converter is part of the
exhaust system front downpipe - see Chap-
ter 4 for details of removal and refitting.
6•20 Emissions control systems
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11Locate one of the circlips in the outer
groove of the knuckle.
12Press or drive the new bearing into the
knuckle until it contacts the circlip, using a
length of metal tube of diameter slightly less
than the outer race. Do not apply any
pressure to the inner race.
13Locate the remaining circlip in the inner
groove of the knuckle.
14Support the inner race on a length of
metal tube, then press or drive the hub fully
into the bearing.
15Refit the steering knuckle and hub
assembly as described in Section 2.
Removal
1Apply the handbrake, then jack up the front
of the vehicle and support it on axle stands.
Remove the appropriate front wheel.
2Unbolt the brake hose support bracket from
the front of the suspension strut (see
illustration).
3Remove the brake caliper as described in
Chapter 9, but do not disconnect the flexible
hydraulic hose from the caliper. Suspend the
caliper from a suitable point under the wheel
arch, taking care not to strain the hose.
4Extract the split pin from the track rod end
balljoint nut. Unscrew the nut, and detach the
rod from the arm on the steering knuckleusing a conventional balljoint removal tool.
Take care not to damage the balljoint seal.
5Remove the ABS sensor (when fitted) from
the steering knuckle, as described in Chapter 9.
6Remove the clip securing the driveshaft
inner gaiter to the inner CV joint. Disconnect
the gaiter from the CV joint housing.
7Remove the nut and disconnect the anti-roll
bar link from the strut. Note that, on models
fitted with ABS, the ABS wheel sensor wiring
support bracket is located beneath the nut
(see illustration).
8Note which way round the lower arm
balljoint clamp bolt is fitted, then unscrew and
remove it from the knuckle assembly. Lever
the balljoint down from the knuckle; if it is
tight, prise the clamp open carefully using a
large flat-bladed tool. Take care not to
damage the balljoint seal during the
separation procedure.
9Where applicable, disconnect the adaptive
damping wiring multi-plug at the strut, and
unclip the wire.
10Support the strut and steering knuckle on
an axle stand. Working inside the engine
compartment, remove the strut cap (if fitted).
Unscrew and remove the front suspension
strut upper mounting nut, holding the piston
rod stationary with an 8 mm Allen key (see
illustration).
11Lower the suspension strut, together with
the driveshaft and steering knuckle, from
under the wheel arch, withdrawing the tripod
on the inner end of the driveshaft from the CV
joint housing.12Unscrew and remove the pinch-bolt
securing the steering knuckle assembly to the
front suspension strut, noting which way
round it is fitted. Prise open the clamp using a
wedge-shaped tool, and release the knuckle
from the strut (see illustrations).
Refitting
13With the clamp prised open, locate the
front suspension strut on the steering knuckle,
and refit the pinch-bolt with its head facing
forwards. Tighten the bolt to the specified
torque.
14Locate the suspension strut (together with
the driveshaft and steering knuckle) in its
upper mounting, and loosely screw on the
nut.
15Locate the tripod on the inner end of the
driveshaft in the CV joint housing, then
manipulate the gaiter onto the housing, and fit
a new clip.
16Where applicable, reconnect the adaptive
damping multi-plug, and fit the wire in the clip.
17Locate the lower arm balljoint fully in the
bottom of the steering knuckle. Refit the
clamp bolt and tighten it to the specified
torque.
18Reconnect the anti-roll bar link to the
strut, and tighten the nut to the specified
torque. On models fitted with ABS, do not
forget to locate the sensor wiring support
bracket beneath the nut.
19Where fitted, refit the ABS sensor as
described in Chapter 9.
20Refit the track rod end balljoint to the
steering knuckle, and tighten the nut to the
specified torque. Check that the split pin
holes are aligned; if necessary, turn the nut to
the nearest alignment, making sure that the
torque wrench setting is still within the
specified range. Insert a new split pin, and
bend it back to secure.
21Refit the brake caliper as described in
Chapter 9.
22Refit the brake hose support bracket to
the strut, and tighten the bolt.
23Refit the wheel, and lower the vehicle to
the ground. Tighten the wheel nuts to the
specified torque.
24Tighten the suspension strut upper
mounting nut to the specified torque, while
4 Front suspension strut -
removal and refitting
10•6 Suspension and steering systems
4.2 Removing the brake hose support
bracket from the front of the front
suspension strut4.7 Removing the anti-roll bar link and
ABS sensor wiring bracket4.10 Front suspension strut upper
mounting nut
4.12A Steering knuckle-to-strut pinch-bolt4.12B Releasing the knuckle from the strut
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spring must now be carefully released from
the compressor. If it is to be re-used, the
spring can be left in compression.
7With the strut assembly now completely
dismantled, examine all the components for
wear and damage, and check the bearing for
smoothness of operation. Renew components
as necessary.
8Examine the strut for signs of fluid leakage.
Check the strut piston for signs of pitting
along its entire length, and check the strut
body for signs of damage. Test the operation
of the strut, while holding it in an upright
position, by moving the piston through a full
stroke, and then through short strokes of 50
to 100 mm. In both cases, the resistance felt
should be smooth and continuous. If the
resistance is jerky, uneven, or if there is any
visible sign of wear or damage to the strut,
renewal is necessary.
9Reassembly is a reversal of dismantling,
noting the following points:
(a) Make sure that the coil spring ends are
correctly located in the upper and lower
seats before releasing the compressor.
(b) Check that the bearing is correctly fitted
to the piston rod seat.
(c) Tighten the thrust bearing retaining nut to
the specified torque.
Removal
1Apply the handbrake, jack up the front of
the vehicle and support it on axle stands.
Remove both front wheels.
2Unscrew the nuts, and disconnect the anti-
roll bar links from the front suspension struts
on both sides of the vehicle. Note that, on
models with ABS, the wheel sensor wiring
support brackets are located beneath the nuts
(see illustrations).
3Unscrew and remove the anti-roll bar
mounting bolts from the engine subframe on
both sides of the vehicle.
4Withdraw the anti-roll bar from one side of
the vehicle, taking care not to damage the
surrounding components.5If necessary, unscrew the nuts and remove
the links from the anti-roll bar.
Refitting
6Refitting is a reversal of the removal
procedure.
Removal
1Apply the handbrake, jack up the front of
the vehicle and support it on axle stands.
Remove the appropriate wheel.
2If removing the right-hand side lower arm,
remove the auxiliary drivebelt cover where
necessary.
3Unscrew and remove the nuts and bolts
securing the lower arm to the subframe (see
illustration).
4Unscrew the nuts and disconnect the anti-
roll bar links from the anti-roll bar on both
sides. Swivel the anti-roll bar upwards away
from the lower arm.
5Extract the split pin from the track rod end
balljoint nut. Unscrew the nut, and detach the
rod from the arm on the steering knuckle
using a conventional balljoint removal tool.
Take care not to damage the balljoint seal.
6Remove the clip securing the driveshaft
inner gaiter to the inner CV joint, and
disconnect the gaiter from the CV joint
housing. This is necessary to prevent damageto the gaiter when the steering knuckle is
moved outwards to remove the lower arm.
7Note which way round the front suspension
lower arm balljoint clamp bolt is fitted, then
unscrew and remove it from the knuckle
assembly. Lever the balljoint down from the
knuckle; if it is tight, prise the joint open carefully
using a large flat-bladed tool. Take care not to
damage the balljoint seal during the separation
procedure. Support the inner end of the
driveshaft on an axle stand (see illustrations).
8Remove the lower arm from the subframe,
and withdraw it from the vehicle.
Overhaul
9Examine the rubber bushes and the
suspension lower balljoint for wear and
damage. The balljoint may be renewed as
described in Section 8. The rubber bushes
may be removed using a press, or a length of
metal tubing together with a long bolt,
washers and nut.
10Note that the front and rear bushes are
different. The front one has a solid rubber
bush with a cylindrical inner tube, whereas the
rear one has a voided rubber bush with a
barrel-shaped inner tube (see illustration).
11Press the new bushes into the lower arm,
using the same method as used for removal.
Note that, when fitting the rear bush, the voids
must be in line with the front bush location.
On later models, a pip on the rear bush must
be aligned with a triangular alignment mark on
the arm.
7 Front suspension lower arm -
removal, overhaul and refitting
6 Front anti-roll bar and links -
removal and refitting
10•8 Suspension and steering systems
6.2A Unscrew the nut . . .6.2B . . . and disconnect the anti-roll bar
link and (on ABS models) the sensor wiring
support bracket
7.3 One of the nuts and bolts securing the
lower arm to the subframe7.7A Unscrew the lower arm balljoint
clamp bolt . . .7.7B . . . and disconnect the balljoint from
the knuckle
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15Locate the steering column shaft on the
flexible coupling, swivel the clamp plate
round, then insert the bolt and tighten to the
specified torque.
16Refit the driver’s side lower trim panel.
17Refit the steering column upper and lower
shrouds.
18Reconnect the battery negative lead.
Removal
1Disconnect the battery negative (earth) lead
(refer to Chapter 5, Section 1).
2Turn the steering wheel so that the front
wheels are in the straight-ahead position.
Remove the ignition key, then turn the
steering wheel slightly as necessary until the
steering lock engages.
3Unscrew the clamp plate bolt securing the
steering column shaft to the flexible coupling.
Swivel the clamp plate around, and disengage
it from the flexible coupling stub.
4Carefully prise the rubber boot from the
bulkhead, and withdraw it into the passenger
compartment. Take care not to damage the
sealing lip of the boot.
5Using an Allen key, unscrew the clamp bolt
securing the flexible coupling to the pinion
shaft on the steering gear, and withdraw the
coupling from inside the vehicle.
Refitting
6Refitting is a reversal of the removal
procedure, but tighten the clamp bolts to the
specified torque. Make sure that the rubber
boot engages correctly in the bulkhead and
on the flexible coupling.
Removal
1Remove the steering column flexible
coupling as described in Section 29.
2Apply the handbrake, then jack up the frontof the vehicle and support it on axle stands.
Remove both front wheels.
3Working beneath the vehicle, unbolt the
rear engine mounting from the transmission
and underbody.
4Extract the split pins from the track rod end
balljoint nuts, then unscrew the nuts, and
detach the rods from the arms on the steering
knuckles using a conventional balljoint
removal tool. Take care not to damage the
balljoint seals.
5Position a suitable container beneath the
steering gear, then unscrew the union nuts
securing the power steering fluid supply,
return, and cooler lines to the steering gear.
Identify the lines for position, then unbolt the
clamps, disconnect the lines, and allow the
fluid to drain into the container. Cover the
apertures in the steering gear and also the
ends of the fluid pipes, to prevent the ingress
of dust and dirt into the hydraulic circuit.
6Unscrew and remove the steering gear
mounting bolts. The bolts are located on top
of the steering gear, and are difficult to reach.
Ideally, the special U-shaped Ford spanner
should be used, but it is just possible to reach
them with a normal spanner (see illustration).
7Withdraw the steering gear through the
wheel arch.
Refitting
8If the steering gear is being replaced with a
new one, the new unit will be supplied
together with union nuts already fitted. The
new nuts must only be used with new feed
and return lines - otherwise, they must be
removed and discarded. If the original lines
and union nuts are being used, the Teflon
rings on the union nuts must be renewed. To
do this, the rings must be expanded
individually onto a fitting adaptor (see
illustration), then located in the grooves of
the union nuts.
9Locate the steering gear on the subframe,
and insert the two mounting bolts. Tighten the
bolts to the specified torque (see illustration).
Note that, if the special Ford tool is being
used, the bottom of the tool must be turned
anti-clockwise in order to tighten the
mounting bolts.10Remove the covers from the apertures on
the steering gear, then reconnect the fluid
lines and tighten the union nuts to the
specified torque. Refit the clamps and tighten
the bolts.
11Refit the track rod end balljoints to the
steering knuckles, and tighten the nuts to the
specified torque. Check that the split pin
holes are aligned; if necessary, turn the nuts
to the nearest alignment, making sure that the
torque wrench setting is still within the
specified range. Insert new split pins, and
bend them back to secure.
12Refit the rear engine mounting to the
transmission and underbody, and tighten the
bolts to the specified torque.
13Refit the front wheels, and lower the
vehicle to the ground.
14Refit the steering column flexible coupling
with reference to Section 29.
15Bleed the power steering hydraulic
system as described in Section 33.
16Have the front wheel alignment checked,
and if necessary adjusted, at the earliest
opportunity (refer to Section 36).Removal
1Disconnect the battery negative (earth) lead
(refer to Chapter 5, Section 1).
2Working inside the vehicle, unscrew the
clamp plate bolt securing the steering column
shaft to the flexible coupling. Swivel the clamp
plate around, and disengage it from the
flexible coupling stub.
3Apply the handbrake, then jack up the front
of the vehicle and support it on axle stands.
Remove both wheels.
4On manual transmission models,
disconnect the gearchange linkage and
support rods from the transmission, as
described in Chapter 7, Part A.
5Remove the exhaust downpipe complete,
as described in Chapter 4.
6Remove the cover from under the radiator
by unscrewing the screws and releasing the
clips.
31 Power steering gear
(left-hand-drive models with
ABS) - removal and refitting
30 Power steering gear (all except
left-hand-drive models with
ABS) - removal and refitting
29 Steering column flexible
coupling - removal and refitting
10•20 Suspension and steering systems
30.6 U-shaped Ford spanner for
unscrewing the steering gear mounting
bolts
30.8 Using an adaptor to fit the Teflon
rings to the union nuts
1 Adaptor 2 Teflon ring 3 Union nut
4 Groove location for the Teflon ring
30.9 Tightening the steering gear
mounting bolts using the U-shaped
spanner (arrowed)
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