
19Disconnect the wiring connectors from the
ignition distributor and the fuel temperature
sensor (see illustrations).
20Release the pressure in the fuel distributor
pipe by depressing the pin in the vent valve.
Cover the valve with a rag during this
operation to prevent fuel being sprayed out
(see illustration).
21Disconnect the fuel lines (see illustration).
22Disconnect the vacuum hoses from the
following components:
a)Fuel pressure regulator.
b)Throttle valve assembly.
c)T-piece connector (see illustration).
23Disconnect the rocker cover breather hose
(see illustration).
24Unbolt the plenum chamber and place it to
one side with the throttle cable attached.25Disconnect the HT leads from the spark
plugs and the ignition coil noting their correct
fitted locations. Undo the two retaining screws
then remove the distributor cap and HT leads
as an assembly.
26Using a 19 mm socket on the crankshaft
damper centre bolt, set No 1 piston to its firing
point (12°BTDC) and remove the distributor.
27If the right-hand cylinder head is to be
removed, remove the drivebelts, unbolt the
alternator and power steering pump and tie
them to one side of the engine compartment.
28Unbolt and remove the rocker cover(s).
29Unbolt and remove the rocker shaft(s) (see
illustration).
30Withdraw the pushrods and keep them in
their originally fitted sequence.
31Disconnect the inlet manifold to timingcover coolant hose from the manifold.
32Unbolt and remove the inlet manifold
complete with fuel rail and injectors. Discard
the gasket.
33Disconnect the exhaust downpipe(s) from
the manifold(s).
34Disconnect the earth straps from the rear
of the left-hand cylinder head and release the
cable retaining clamp.
35Unscrew and remove the spark plugs.
36Unscrew the cylinder head bolts using the
reverse of the tightening sequence (see
illustration 38.5). Obtain new bolts for refitting.
Remove the cylinder head(s) and discard the
gasket(s).
Proceed as described in Part A, Section 16
of this Chapter but note that there are 24 bolts
retaining the sump, not 23.
The procedure is described for the engine in
the vehicle. With the engine removed, the
preliminary steps can be ignored.
2.8 litre engine
1Disconnect the battery negative lead.
2Drain the engine oil.
3Drain the coolant and remove the radiator.
10Timing cover and drive -
removal
9Sump - removal
V6 engines 2C•9
2C
8.18b Disconnecting the idle speed control
valve wiring plug8.19a Disconnecting the distributor wiring
plug8.19b Disconnecting the fuel temperature
sensor wiring plug
8.22 Vacuum hose T-piece connector
8.20 Fuel rail vent (depressurising) valve
and cap8.21 Fuel feed (A) and return (B) hoses
8.23 Rocker cover breather hose (arrowed)8.29 Removing rocker shaft and pedestal
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6Lubricate the pushrods with engine oil and
insert them in the cylinder block.
7Place the oil splash shields in position on
the cylinder heads and fit the rocker shaft
assemblies. Guide the rocker arm adjusting
screws into the pushrod sockets (see
illustrations).
8Tighten the rocker shaft securing bolts
progressively to the specified torque.
9Refit the inlet manifold, using a new gasket.
Do not refit the rocker covers yet.
10Adjust the valve clearances (Section 39).
11Refit the spark plugs.
12Refit the rocker covers, using new
gaskets. The adhesive side of the gaskets
should face the rocker cover.
13If the engine is in the vehicle, reverse the
preliminary steps.2.4 & 2.9 litre engines
14Refitting the cylinder heads to these
engines is essentially a reversal of the removal
procedure but also refer to information given
for the 2.8 litre engine whilstnoting the
following points.
15Always use new Torx type cylinder head
bolts. Oil them and allow them to drain. When
fitted the word OBEN should be visible on the
new gaskets.
16Tighten the bolts in the specified
sequence (as for the 2.8 litre engine) to the
correct torque. The final stage in the tightening
procedure is by the angular method. Use a
disc similar to the one shown or make a paint
mark at the same point on each bolt head to
ensure that each bolt is turned through exactly
the same number of degrees (see
illustration).17As a result of the bolt tightening torque
used and the elasticity of the bolts, no further
tightening is required after the initial running-in
period.
18Apply jointing compound to the areas
where the inlet manifold and cylinder heads
meet and locate a new gasket in position.
Make sure that it is the correct way around.
Tighten the inlet manifold bolts to the specified
torque and in the sequence shown (see
illustrations).
19Check that No 1 piston is still at the firing
point (12°BTDC) and fit the distributor.
20Adjust the valve clearances.
21Fit new rocker cover gaskets, peeling off
the self-adhesive shield before sticking the
gaskets to the covers. Note the aluminium
spacers in the gaskets to prevent
overtightening (see illustration).
22Use a new gasket at the plenum chamber
and tighten the fixing bolts to the specified
torque (see illustration).
23Refit the alternator and power steering
pump (where removed) and tension the
drivebelts.
24Reconnect the fuel lines and secure them
in position with new clips. Reconnect all
coolant and vacuum hoses and electrical
connectors. Refill the engine with coolant and
reconnect the battery.
25Switch on the ignition and bleed the fuel
system by operating the vent valve on the fuel rail.
26Run the engine up to normal operating
temperature and then check the ignition
timing.
2C•20V6 engines
38.7a Fitting the pushrods and oil splash
shields
38.18a Inlet manifold gasket correctly
located38.18b Fitting inlet manifold complete with
fuel rail and injectors
38.22 Lowering the plenum chamber into
position38.18c Inlet manifold tightening sequence
Arrow indicates the front of the engine38.21 Peeling off rocker cover gasket
protective shield
38.7b Fitting an assembled rocker shaft38.16 Tightening a cylinder head bolt using
an angular tightening disc
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27The inlet manifold bolts should be
retightened to the specified torque in the correct
sequence. This will mean disconnecting the air
hoses from the throttle valve housing, the
vacuum hose from the left-hand rocker cover,
and the wiring connector from the idle speed
control valve and throttle valve potentiometer.
Remove the plenum chamber, place it to one
side, then release the fuel rail bolts but do not
disconnect the fuel pipes. It may also be
necessary to remove the distributor again to
gain access to one of the bolts.
See Chapter 1, Section 23.
1Refer to Section 7 and refit the items listed.
2If the oil cooler and its threaded bush were
removed, refit them as follows (see
illustration).
3Screw the new bush into the cylinder block.
Apply Omnifit Activator “Rapid” (to Ford
specification SSM-99B-9000-AA) to the
exposed threads of the bush and to the inside
of the threaded sleeve.
4Apply one drop of Omnifit Sealant “300
Rapid” (to Ford specification SSM-4G-9003-
AA) to the leading threads of the bush.Do not
use more than one drop, otherwise sealant
may get into the lubrication circuit.
5Fit the cooler, using a new gasket, and
secure with the threaded bush. Make sure that
the coolant pipes are positioned at the correct
angle (see illustration),then tighten the
threaded sleeve to the specified torque.
6Fit a new oil filter element, oiling its sealing
ring prior to installation. Tighten the filter
approximately three-quarters of a turn beyond
the point where the seal contacts the cooler
face. Do not use any tool to tighten the filter.
Refer to Part A, Section 49, paragraphs 1 to
9 of this Chapter. Before starting the engine,
refer to the following Section.1Refer to Part A, Section 51 of this Chapter.
2When conventional (hexagon-headed)
cylinder head bolts are fitted, they must be re-
tightened after the engine has warmed up.
Proceed as follows.
3Stop the engine and remove the rocker covers.
4Working in the sequence used for
tightening, slacken one cylinder head bolt a
quarter turn, then re-tighten it to the Stage 4
specified torque. Repeat in sequence for all
the cylinder head bolts.
5Tighten the inlet manifold bolts.
6Check the valve clearances.
7Refit the rocker covers and other disturbed
components.
1When engine performance is down, or if
misfiring occurs which cannot be attributed to
the ignition or fuel system, a compression test
can provide diagnostic clues. If the test is
performed regularly it can give warning of
trouble before any other symptoms become
apparent.
2The engine must be at operating
temperature, the battery must be fully charged
and the spark plugs must be removed. The
services of an assistant will also be required.3Disable the ignition system by dismantling
the coil LT feed. Fit the compression tester to
No 1 spark plug hole. (The type of tester which
screws into the spark plug hole is to be
preferred.)
4Have the assistant hold the throttle wide
open and crank the engine on the starter.
Record the highest reading obtained on the
compression tester.
5Repeat the test on the remaining cylinders,
recording the pressure developed in each.
6Desired pressures are given in the
Specifications. If the pressure in any cylinder
is low, introduce a teaspoonful of clean engine
oil into the spark plug hole and repeat the test.
7If the addition of oil temporarily improves
the compression pressure, this indicates that
bore or piston wear was responsible for the
pressure loss. No improvement suggests that
leaking or burnt valves, or a blown head
gasket, may be to blame.
8A low reading from two adjacent cylinders is
almost certainly due to the head gasket
between them having blown.
9On completion of the test, refit the spark
plugs and reconnect the coil LT feed.
43Compression test -
description and interpretation
42Initial start-up after overhaul
or major repair
41Engine - refitting
40Ancillary components - refitting
39Valve clearances - checking
and adjustment
V6 engines 2C•21
2C
40.2 Oil cooler components
A Threaded bush
B Seal
C CoolerD Sleeve
E Oil filter
40.5 Oil cooler installation angle
A Rear face of cylinder block
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The exhaust system fitted in production is
made of aluminised steel, with stainless steel
used in the endplates and baffles of the rear
silencer. Individual sections of the system are
easily renewed in service.
Emission control for the UK market is
achieved largely by the inherent efficiency of
the fuel, ignition and engine management
systems. A welcome spin-off from such
efficiency is remarkably good fuel economy for
a vehicle of such size and weight.
Precautions
Fuel
Many of the procedures in this Chapter
require the removal of fuel lines and
connections which may result in some fuel
spillage. Residual pressure in fuel-injection
systems will remain in the fuel lines long after
the vehicle was last used, therefore extra care
must be taken when disconnecting a fuel line
hose. Loosen any fuel hose slowly to avoid a
sudden release of pressure which may cause
fuel spray. As an added precaution place a rag
over each union as it is disconnected to catch
any fuel which is forcibly expelled. Before
carrying out any operation on the fuel system
refer to the precautions given in “Safety first!”
at the beginning of this Manual and follow
them implicitly. Petrol is a highly dangerous
and volatile liquid and the precautions
necessary when handling it cannot be
overstressed
Tamperproof adjustment screws
Certain adjustment points in the fuel system
(and elsewhere) are protected by tamperproof
caps, plugs or seals. The purpose of such
tamperproofing is to discourage, and to deter,
adjustment by unqualified operators.
In some EU countries (though not yet in the
UK) it is an offence to drive a vehicle with
missing or broken tamperproof seals. Before
disturbing a tamperproof seal, satisfy yourself
that you will not be breaking local or national
anti-pollution regulations by doing so. Fit a
new seal when adjustment is complete when
this is required by law.
Do not break tamperproof seals on a vehicle
which is still under warranty.
Catalytic converter
The 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 the full service life.
a)DO NOT use leaded petrol in a car
equipped with a catalytic converter the
lead will coat the precious metals,
reducing their converting efficiency and
will eventually destroy the converter.
b)Always keep the ignition and fuel systems
well-maintained in accordance with the
manufacturer’s schedule - particularly,
ensure that the air cleaner filter element,
the fuel filter and the spark plugs are
renewed at the correct interval - if the inletair/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 car 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
overheating, as noted above.
d)DO NOT push- or tow-start the car - this
will soak the catalytic converter in
unburned fuel, causing it to overheat when
the engine does start - see b) above.
e)DO NOT switch off the ignition at high
engine speeds - if the ignition is switched
off at anything above idle speed,
unburnedfuel will enter the (very hot)
catalytic converter, with the possible risk
of igniting on the element and damaging
the converter.
f)DO NOT use fuel or engine oil additives -
these may contain substances harmful to
the catalytic converter.
g)DO NOT continue to use the car if the
engine burns oil to the extent of leaving a
visible trail of blue smoke - the unburned
carbon deposits will clog the converter
passages and reduce the efficiency; in
severe cases the element will overheat.
h)Remember that the catalytic converter
operates at very high temperatures -
hence the heat shields on the car’s
underbody and the casing will become hot
enough to ignite combustible materials
which brush against it - DO NOT,
therefore, park the car in dry undergrowth,
over long grass or piles of dead leaves.
i)Remember that the catalytic converter is
FRAGILE, do not strike it with tools during
servicing work, take great care when
working on the exhaust system, ensure
that the converter is well clear of any jacks
or other lifting gear used to raise the car
and do not drive the car over rough
ground, road humps, etc, in such a way as
to “ground” the exhaust system.
j)In some cases, particularly when the car is
new and/or is used for stop/start driving, a
sulphurous smell (like that of rotten eggs)may be noticed from the exhaust. This is
common to many catalytic converter-
equipped cars 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 car 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.
k)The catalytic converter, used on a well-
maintained and well-driven car, should
last for between 50 000 and 100 000 miles
- from this point on, careful checks should
be made at all specified service intervals
of the CO level to ensure that the
converter is still operating efficiently - if
the converter is no longer effective it must
be renewed.
See Chapter 1, Section 38.
1On carburettor models only, the air cleaner
can take in both hot and cold air. Hot air is
obtained from a shroud bolted to the exhaust
manifold.
2A flap valve in the air cleaner spout
determines the mix of hot and cold air. The
valve is operated by a vacuum diaphragm.
Vacuum is obtained from the inlet manifold
and is applied via a heat-sensing valve, which
cuts off the vacuum as the temperature of the
incoming air rises. Thus the air cleaner takes in
only hot air on starting from cold, changing
progressively to cold air as the engine warms
up (see illustrations).
3If the system fails, either the engine will take
a long time to warm up (flap stuck in “cold”
position), or it may run roughly and not
develop full power when warm (flap stuck in
“hot” position). Check it as follows.
3Air cleaner temperature control
- description and testing
2Air cleaner and element -
removal and refitting
4•4Fuel and exhaust systems
3.2b Air cleaner heat sensor3.2a Air cleaner vacuum diaphragm unit
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4With the engine cold, disconnect the cold
air inlet trunking from the spout. Look into the
spout and check that the flap valve is covering
the hot air inlet.
5Start the engine and allow it to idle. Check
that the flap moves to cover the cold air inlet. If
the flap does not move, check the diaphragm
and heat sensor as follows.
6Stop the engine. Disconnect the diaphragm
vacuum pipe from the heat sensor. Apply
vacuum to the diaphragm, using a vacuum
head pump or by connecting the pipe directly
to manifold vacuum. If the flap now moves, the
heat sensor or vacuum line was faulty. If the
flap still does not move, the diaphragm is
faulty or the flap is jammed.
7On completion reconnect the vacuum pipe
and the cold air trunking.
Mechanical
1Carburettor models without air conditioning
are fitted with a mechanical fuel pump, located
on the left-hand side of the engine block.
2To test the pump, disconnect the ignition
coil LT lead. Disconnect the outlet hose from
the pump and place a wad of rag next to the
pump outlet. Take appropriate fire
precautions.
3Have an assistant crank the engine on the
starter. Well-defined spurts of fuel must beejected from the pump outlet - if not, the pump
is probably faulty (or the tank is empty).
Dispose of the fuel-soaked rag safely.
4To remove the fuel pump, first disconnect
the battery negative lead.
5Disconnect and plug the pump inlet and
outlet hoses. Be prepared for fuel spillage.
6Unscrew the two bolts and withdraw the
pump from the cylinder block. Remove the
gasket. If necessary extract the pushrod (see
illustrations).
7Clean the exterior of the pump in paraffin
and wipe dry. Clean all traces of gasket from
the cylinder block and pump flange.
8If the fuel pump has a removable cover,
remove the screw and withdraw the cover and
nylon mesh filter with seal (see illustrations).
Clean the filter, cover and pump in fuel. Locate
the filter in the cover and fit the cover to the
pump so that the pipe and indentation are
aligned. Tighten the screw.
9Refitting is a reversal of removal, but fit a
new gasket and tighten the bolts to the
specified torque. If necessary discard the
crimped type hose clips and fit screw type
clips.
Electrical
SOHC and 2.8 litre V6 engines
10All fuel-injection models, and carburettor
models when fitted with air conditioning, have
an electric fuel pump. The two types of pump
are not the same, although both are mounted
under the vehicle next to the fuel tank.11If the fuel pump appears to have failed
completely, check the appropriate fuse and
relay. On fuel-injection models, also check the
inertia switch (when fitted).
12To test the carburettor type pump,
disconnect the fuel supply hose from the
pressure regulator or vapour separator in the
engine compartment. Lead the hose into a
measuring cylinder.
13Take appropriate fire precautions. Switch
on the ignition for 30 seconds and measure
the quantity of fuel delivered: it should be at
least 400 cc (0.7 pint).
14To test the fuel-injection type pump,
special equipment is required. Consult a Ford
dealer or other fuel-injection specialist. The
problem may be due to a clogged filter.
15To remove a pump, first disconnect the
battery negative lead. Take appropriate fire
precautions.
16Raise and support the rear of the vehicle.
Clean the fuel pump and its surroundings.
17Clamp the tank-to-pump hose, or make
arrangements to collect the contents of the
fuel tank which will otherwise be released.
18Place a drain pan beneath the pump.
Disconnect the inlet and outlet hoses; be
prepared for fuel spillage. Caution: Fuel under
pressure may spray out of the outlet hose
union as it is slackened.
19Disconnect the wiring plug from the pump.
20Slacken the pump bracket clamp bolt and
slide the pump out of the bracket.
21Refit by reversing the removal operations.
Make sure that all hoses and unions are in
good condition.
22On2.4 & 2.9 litre V6 engines up to mid-
1990, switch the ignition on and off five times,
without cranking the engine, to pressurise the
fuel system then check the pump unions for
signs of leakage.
23Run the engine and check for leaks.
DOHC engine
24On these models the fuel pump is
mounted in the fuel tank, on the same
mounting as the fuel level sender unit(see
illustration).To test the pump specialist
equipment is required, therefore this task must
be entrusted to a Ford dealer.
4Fuel pump - testing, removal
and refitting
Fuel and exhaust systems 4•5
4
4.6a Removing the mechanical fuel pump4.6b Fuel pump pushrod
4.8a Removing the fuel pump cover - note
alignment indentations4.8b Fuel pump cover and filter screenA Fuel pumpB Fuel level sender unit
4.24 Combined fuel pump/fuel level sender
unit
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7Disconnect and plug the automatic choke
coolant hoses (see illustration). Be prepared
for coolant spillage.
8Remove the three Torx screws which secure
the carburettor to the manifold (see
illustration).
9Check that no attachments have been
overlooked, then lift the carburettor off the
manifold. Recover the gasket.
10Clean the carburettor and manifold matingsurfaces, being careful not to get dirt into the
manifold.
11Refit by reversing the removal operations.
Top-up the cooling system if necessary on
completion, then check the idle speed and
mixture.
12On engines from September 1986, a
modified carburettor was fitted which
incorporates a secondary choke pull-down
diaphragm that assists in reducing fuel
consumption (see illustration).If such a
replacement carburettor is to be fitted to
earlier models, always use a new mountinggasket and also carry out the following
operations.
a)Obtain the special wiring loom and connect
the wiring connector(see illustration).
b)Disconnect the positive feed wire from the
ignition coil and then connect the leads of
the new loom to the positive terminal of the
coil and the end of the disconnected
positive feed wire.
c)Connect the loom earth eyelet to one of the
ignition coil retaining screws.
d)After fitting the air cleaner, check the
carburettor settings (Section 11).
4•8Fuel and exhaust systems
12.5 Crimped hose clip (arrowed) must be
renewed
12.12 Pierburg 2V carburettor fitted to later
1.8 litre engines
A Fuel inlet hose
B Swivel clip location
C Diaphragm hose
D Diaphragm (secondary choke pulldown)
12.13 Wiring connections to Pierburg 2V
carburettor fitted to later 1.8 litre engines
A Loom
B Secondary choke pulldown diaphragm
C Earth
D Original coil connector
12.7 Disconnecting a coolant hose from the
automatic choke12.8 Undoing a carburettor securing screw.
Other two screws are arrowed
13.4 Exploded view of Pierburg 2V carburettor
A Bi-metal housing
B O-ring
C Water jacket
D Pull-down diaphragm
unit
E Secondary throttle
diaphragm unit
F Idle speed adjustment
screw
G Accelerator pump
diaphragm
H Power valve
J Throttle damper (not
all models)
K Carburettor body
L Fuel inlet pipe and
filter
M Primary main jet
N Secondary
main jet
O Top cover
P Idle jet
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16Start the engine and note the engine
speed (rpm). The engine speed should
increase above the normal idle speed, and
should be as given in the Specifications.
17If the engine speed is not as specified,
remove the tamperproof plug from the top of
the throttle kicker housing, and turn the
adjustment screw to give the specified speed.
18On completion of adjustment, fit a new
tamperproof cap.
19Disconnect the tubing from the inlet
manifold, and reconnect the throttle kicker
vacuum hose.
20Refit the plastic shield and the air cleaner.
On 2.4 & 2.9 litre V6 models especially,
residual pressure will remain in the fuel lines
long after the vehicle was last used therefore
the fuel system must be depressurised before
any hose is disconnected; the system is
depressurised via the vent valve on the fuel
rail, noting that it may be necessary to depress
the valve several times before the pressure is
fully released. As an added precaution place a
rag over the valve as it is depressed to catch
any fuel which is forcibly expelled. Before
carrying out any operation on the fuel system
refer to the precautions given in Safety first! at
the beginning of this Manual and follow them
implicitly. Petrol is a highly dangerous and
volatile liquid and the precautions necessary
when handling it cannot be overstressed.
Access to the relays is obtained by
removing the facia top cover (crash pad).
The relays are located on the passenger
side(see illustration). Also see Chapter 13,
Section 16.
See Chapter 1, Section 41.
SOHC and 2.8 litre V6 engines
1Idle speed is controlled by the EEC IV
module and no direct adjustment is possible.
2Idle mixture adjustment should not be
necessary on a routine basis. After component
renewal or a similar circumstance it may be
checked and adjusted as follows.
3The engine must be at operating temperature.
The valve clearances must be correct, the air
cleaner element must be clean and the ignition
system must be in good condition.
4Connect an exhaust gas analyser (CO
meter) and a tachometer (rev. counter) to the
engine as instructed by their makers.
5Run the engine at 3000 rpm for 15 seconds,
then allow it to idle. Repeat the procedure
every 60 seconds until adjustment is
complete.
6With the engine idling after the 3000 rpm
burst, record the CO level when the reading
has stabilised. The desired value is given in the
Specifications.
7If adjustment is necessary, remove the
tamperproof plug from the mixture adjusting
screw on the underside of the vane airflow
meter (see illustration).
8On V6 models, note that adjustment should
first be carried out on the front airflow meter.The rear meter should only be adjusted if the
range of adjustment on the front meter is
insufficient.
9Turn the mixture adjusting screw with a
hexagon key until the CO level is correct (see
illustration).
10Stop the engine and disconnect the test
gear.
11Fit a new tamperproof plug if required.
DOHC engine
Note: Before carrying out any adjustments
ensure that the ignition timing and spark plug
gaps are as specified. To carry out the
adjustments, an accurate tachometer and an
exhaust gas analyser (CO meter) will be
required.
12Idle speed is controlled by the EEC IV
module, and manual adjustment is not possible,
although the “base” idle speed can be adjusted
by a Ford dealer using special equipment.
13On models with a catalytic converter, the
mixture is controlled by the EEC IV module,
and no manual adjustment is possible.
14On models without a catalytic converter,
the idle mixture can be adjusted as follows.
15Run the engine until it is at normal
operating temperature.
16Stop the engine and connect a tachometer
and an exhaust gas analyser in accordance
with the manufacturer’s instructions.
17Start the engine and run it at 3000 rpm
for 15 seconds, ensuring that all electrical
loads (headlamps, heater blower, etc) are
switched off, then allow the engine to idle, and
check the CO content. Note that the reading
will initially rise, then fall and finally stabilise.
18If adjustment is necessary, remove the
cover from the mixture adjustment
potentiometer (located on the right-hand side
of the engine compartment, behind the MAP
sensor), and turn the screw to give the
specified CO content (see illustration).
19If adjustment does not produce a change
in reading, the potentiometer may be at the
extreme of the adjustment range. To centralise
the potentiometer, turn the adjustment screw
20 turns clockwise followed by 10 turns anti-
clockwise, then repeat the adjustment
procedure.
31Fuel-injection system - idle
speed and mixture adjustment
30Fuel filter - renewal
29Fuel-injection system relays -
location
28Fuel-injection system -
depressurisation
4•14Fuel and exhaust systems
31.18 Remove the cover from the mixture
adjustment potentiometer31.9 Idle mixture adjustment - fuel-injection
models
29.2 Fuel injection system relays - 2.4 and
2.9 litre V6 engines
A Power relayB Fuel pump relay
31.7 Tamperproof plug (arrowed) covering
mixture adjusting screw
Airflow meter is inverted for photo
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connector is supplied with a captive “tell-tale”
ring, the purpose being to hold the connector
teeth retracted. When the two halves of the
connector are pressed together, the ring is
ejected to show that the connection has been
successfully made. Fit the fuel pipe connector
clip (see illustrations).
56As soon as the injectors and fuel rail are
installed and the fuel pipes are connected,
connect the battery and switch the ignition on
and off twice, without cranking the engine, to
pressurise the fuel system. With the system
pressurised check all disturbed fuel unions for
leaks.
57Refit and reconnect all other removed and
disconnected components.
58Reconnect the battery.
SOHC and 2.8 litre V6 engines
1Disconnect the battery negative lead.
2On V6 models, unclip the HT leads from the
fuel pressure regulator bracket.
3Place a drain pan or plenty of rags beneath the
regulator, then disconnect the fuel return pipe
(see illustration). Be prepared for fuel spillage.
4Disconnect the vacuum pipe from the
regulator (see illustration).
5Slacken the fuel feed union nut (see
illustration). Wait until any residual fuel
pressure has decayed, then unscrew the nut.
6Unscrew the nut from the base of the
regulator. Remove the regulator.
7When refitting, only tighten the regulator
base nut lightly at first. Secure the fuel feed
union and tighten its nut, then fully tighten the
base nut.
8Reconnect the vacuum and fuel return pipes.
9Remove the drain pan or rags. On V6
models, secure the HT leads to their clip.
10Reconnect the battery. Switch the ignition
on and off five times (without cranking the
engine) and check that there are no fuel leaks
from the regulator.
DOHC engine
11Disconnect the battery negative lead.
12Slowly loosen the fuel rail feed union to
relieve the pressure in the system. Beprepared for fuel spillage, and take adequate
fire precautions.
13Disconnect the fuel return hose from the
pressure regulator (see illustration). Again, be
prepared for fuel spillage.
14Disconnect the vacuum pipe from the top
of the pressure regulator.
15Unscrew the two securing bolts, and
withdraw the regulator from the fuel rail along
with the O-ring seal. Discard the O-ring.
16Fit a new O-ring to the regulator, and
lubricate it with a smear of clean engine oil.
17Fit both the securing bolts to the regulator,
then position the regulator on the fuel rail, and
tighten the securing bolts.
18Further refitting is a reversal of removal,
but if the fuel return line was originally secured
with a crimped-type clip, discard this and use
a new worm drive hose clip.
19On completion, check the fuel line
connections for leaks, pressurising the system
by switching the ignition on and off several times.
2.4 & 2.9 litre V6 engines
20Disconnect the battery negative lead.
21Depressurise the fuel system.
22On models equipped with an aluminium
fuel rail and late level fuel pressure regulator,
remove the fuel return pipe retaining collar
from the top of the regulator.
23On all models, place a suitable container
below the engine to catch any spilt fuel, then
disconnect the fuel return pipe and the
vacuum pipe from the fuel pressure regulator
(see illustration).
37Fuel pressure regulator -
removal and refitting
4•18Fuel and exhaust systems
36.55a Pressing connector together to
eject “tell-tale” ring
37.4 Disconnecting the vacuum pipe from
the fuel pressure regulator
37.5 Slackening the fuel pressure regulator
feed union nut37.13 Disconnect the fuel return hose
(arrowed) from the fuel pressure regulator37.23 Disconnecting the vacuum hose from
the fuel pressure regulator
36.55b Fitting fuel rail connector clip37.3 Disconnecting the fuel return pipe
from the fuel pressure regulator
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