1989 FORD FIESTA steering

8Disconnect the accelerator cable from the
throttle linkage as described in Chapter 4D.
Secure the cable clear of the
engine/transmission.
9 Releasing its wire clip, unplug the wiring
connector from the power steering pressure
switch (where fitted), then disconnect the
earth cable from the engine lifting eye. Refit
the bolt after disconnecting the cable.
10 Marking or labelling all components as
they are disconnected, disconnect the
vacuum hoses as follows:
a) From the rear of the inlet manifold.
b) The braking system vacuum servo unit
hose - from the inlet manifold (see
Chapter 9 for details).
c) While you are there, trace the vacuum line
from the pulse-air filter housing, and
disconnect it from the pulse-air solenoid
valve.
d) Secure all these hoses so that they won’t
get damaged as the engine/transmission
is removed.
11 Unbolt the engine/transmission-to-body earth lead from the transmission
(see
illustration) . Disconnect the speedometer
drive cable (see Chapter 12) and secure it
clear of the engine/transmission.
12 Disconnect the earth strap at the top of
the engine/transmission flange, and the
adjacent bolt securing the wiring harness clip.
13 Where the vehicle is fitted with manual
transmission, disconnect the clutch cable (see
Chapter 6).
14 Marking or labelling all components as
they are disconnected, disconnect the engine
wiring connectors as follows (see
illustrations) :
a) The multi-plug from the E-DIS ignition
coil.
b) The radio interference suppressor from
the DIS ignition coil.
c) The reversing light switch multi-plug.
d) The engine main wiring loom multi-plug
behind the E-DIS ignition coil.
e) The crankshaft speed/position sensor and vehicle speed sensor multi-plugs.
f) The oxygen sensor multi-plug.
15 Unbolt the exhaust manifold heat shield,
and lift it clear.
16 Remove the auxiliary drivebelt (see
Chapter 1).
17 Marking or labelling all components as
they are disconnected and catching as much
as possible of the escaping coolant in the
drain tray, disconnect the cooling system
hoses and pipes as follows:
a) The coolant hoses at the thermostat housing. b)
The coolant hose at the metal cross pipe
lower connection.
c) The radiator top and bottom hoses.
18 Where applicable, detach the power
steering pump pressure pipe clips, release the
unions and disconnect the pump pressure
and return lines. Collect the fluid in a
suitable container, and plug the disconnected
unions.
19 On vehicles fitted with the anti-lock
braking system, refer to Chapter 9 and release
the left-hand modulator from its mounting
bracket, without disconnecting the rigid brake
pipes or return hose. Tie the modulator
securely to the bulkhead.
20 Chock the rear wheels then jack up the
front of the car and support it on axle stands
(see “Jacking and Vehicle Support” ). Remove
the front roadwheels.
21 Refer to Chapter 5 if necessary, and
disconnect the wiring from the starter motor
and alternator.
22 Disconnect the oil pressure switch wiring
connector.
23 On automatic transmission models,
disconnect the starter inhibitor switch wiring
and disconnect the selector cable (see
Chapter 7B). Secure the cable clear of the
engine/transmission.
24 Where the vehicle is fitted with manual
transmission, disconnect the gearchange
linkage and transmission support rod from the
rear of the transmission - make alignment
marks as they are disconnected (see
illustrations) .
Engine removal and overhaul procedures 2D•11
5.14b . . . the radio interference
suppressor . . .5.14a Disconnect the wiring multi-plugfrom the ignition coil . . .5.11 Unbolt the engine/transmission-to-body earth lead from the transmission
5.24b . . . and transmission support rod5.24a Disconnect the gearchange linkage . . .5.14c . . . and the reversing light switch
2D
1595Ford Fiesta Remake
Whenever you disconnect
any vacuum lines, coolant or
emissions hoses, wiring
connectors and fuel lines,
always label them clearly, so that they
can be correctly reassembled. Masking
tape and/or a touch-up paint applicator
work well for marking items. Take
instant photos, or sketch the locations
of components and brackets.
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25On automatic transmission models, clean
around the unions, then disconnect the fluid
pipes from the transmission. Plug the
openings in the transmission and the pipe
unions after removal.
26 Refer to Chapter 10 and remove the front
suspension crossmember.
27 Unscrew the nuts to disconnect the
exhaust system front downpipe from the
manifold. Undo the nuts securing the catalytic
converter to the rear part of the exhaust
system, and remove the converter and
downpipe assembly.
28 On vehicles fitted with the anti-lock braking
system, refer to Chapter 9 and release the
right-hand modulator from its mounting
bracket without disconnecting the rigid brake
pipes or return hose. Tie the modulator
securely to the bulkhead. Additionally, undo
the three bolts securing the modulator bracket.
29 Disconnect both anti-roll bar links from
their respective suspension struts, and both
track rod end ball joints from their spindle
carriers (see Chapter 10).
30 Unscrew the retaining nut and withdraw
the Torx-type clamp bolt securing the lower
suspension arm to the spindle carrier on each
side.
31 Insert a suitable lever between the right-
hand driveshaft inner joint and the
transmission housing, and prise free the
driveshaft from the transmission; be prepared
for oil spillage from the transmission case
through the vacated driveshaft aperture. As it
is being prised free, simultaneously pull the
roadwheel outwards on that side to enable the
driveshaft inboard end to separate from the
transmission. Once it is free, suspend and
support the driveshaft from the steering gear,
to prevent unnecessary strain being placed on
the driveshaft joints.
32 Insert a suitable plastic plug (or if
available, an old driveshaft joint), into the
transmission driveshaft aperture, to
immobilise the gears of the differential unit.
33 Proceed as described above in
paragraphs 31 and 32, and disconnect the
left-hand driveshaft from the transmission.
34 Remove the oil filter, referring to Chapter 1
if necessary.
35 Connect a suitable lift hoist and sling to
the engine, connecting to the lift eyes. When
securely connected, take the weight of the
engine/transmission unit so that the tension is
relieved from the mountings.
36 Unbolt the engine rear right-hand
mounting from the body (one bolt in the wheel
arch, one nut in the engine compartment),
then unbolt the engine front right-hand
mounting from the alternator mounting
bracket. Unbolt the transmission bearer from
the underbody.
37 The engine/transmission unit should now
be hanging on the hoist only, with all
components which connect it to the rest of
the vehicle disconnected or removed, and
secured well clear of the unit. Make a final
check that this is the case. 38
Lower the engine/transmission to the
ground, and withdraw it from under the
vehicle.
39 Referring to the relevant Part of Chapter 7,
separate the transmission from the engine.
40 While the engine/transmission is removed,
check the mountings; renew them if they are
worn or damaged. Similarly, check the
condition of all coolant and vacuum hoses
and pipes (see Chapter 1); components that
are normally hidden can now be checked
properly, and should be renewed if there is
any doubt at all about their condition. Where
the vehicle is fitted with manual transmission,
take the opportunity to overhaul the clutch
components (see Chapter 6). It is regarded by
many as good working practice to renew the
clutch assembly as a matter of course,
whenever major engine overhaul work is
carried out. Check also the condition of all
components (such as the transmission oil
seals) disturbed on removal, and renew any
that are damaged or worn.
Refitting
41 Refitting is a reversal of removal, however
note the following additional points:
a) Refer to the applicable Chapters and Sections as for removal.
b) Fit new spring clips to the grooves in the
inboard end of the right- and left-hand
driveshaft joints. Lubricate the splines
with transmission oil prior to fitting.
c) Renew the exhaust flange gaskets when reconnecting the exhaust. Ensure that all
wires are routed clear of the exhaust
system, and that the heat shields are
securely and correctly fitted.
d) Ensure that all earth lead connections are
clean and securely made.
e) Tighten all nuts and bolts to the specified
torque.
f) Fit a new oil filter, and refill the engine and transmission with oil, with reference to
Chapter 1.
g) Refill the cooling system with reference to
Chapter 1.
h) Bleed the power steering system with reference to Chapter 10.
42 When engine and transmission refitting is
complete, refer to the procedures described
in Section 19 before restarting the engine.
6 Engine overhaul - preliminary information
It is much easier to dismantle and work on
the engine if it is mounted on a portable
engine stand. These stands can often be hired
from a tool hire shop. Before the engine is
mounted on a stand, the flywheel/driveplate
should be removed so that the stand bolts
can be tightened into the end of the cylinder
block/crankcase. If a stand is not available, it is possible to
dismantle the engine with it suitably supported on a sturdy, workbench or on the
floor. Be careful not to tip or drop the engine
when working without a stand.
If you intend to obtain a reconditioned
engine, all ancillaries must be removed first, to
be transferred to the replacement engine (just
as they will if you are doing a complete engine
overhaul yourself). These components include
the following:
a) Alternator/power steering pump and
mounting brackets.
b) DIS/E-DIS ignition coil unit (and mounting
bracket), distributor, HT leads and spark
plugs.
c) The thermostat and housing cover.
d) Carburettor/fuel injection system
components.
e) Inlet and exhaust manifolds.
f) Oil filter.
g) Fuel pump.
h) Engine mountings.
i) Flywheel/driveplate.
j) Water pump.
Note: When removing the external
components from the engine, pay close
attention to details that may be helpful or
important during refitting. Note the fitted
positions of gaskets, seals, washers, bolts and
other small items. If you are obtaining a “short” engine
(cylinder block/crankcase, crankshaft, pistons
and connecting rods all assembled), then the
cylinder head, timing chain/belt (together with
tensioner, tensioner and idler pulleys and
covers) sump and oil pump will have to be
removed also. If a complete overhaul is planned, the
engine can be dismantled in the order given
below, referring to Part A, B or C of this
Chapter unless otherwise stated.
a) Inlet and exhaust manifolds.
b) Timing chain/belt, tensioner and
sprockets.
c) Cylinder head.
d) Flywheel/driveplate.
e) Sump.
f) Oil pump.
g) Pistons (with connecting rods).
h) Crankshaft.
i) Camshaft and tappets (HCS engines).
7 Cylinder head - dismantling
4
Note:New and reconditioned cylinder heads
are available from the manufacturers, and from
engine overhaul specialists. Due to the fact
that some specialist tools are required for the
dismantling and inspection procedures, and
new components may not be readily available,
it may be more practical and economical for
the home mechanic to purchase a
reconditioned head, rather than to dismantle,
inspect and recondition the original head.
1 Remove the cylinder head as described in
Part A, B or C of this Chapter (as applicable).
2D•12 Engine removal and overhaul procedures
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3Accelerator cable (manual
transmission models) -
removal, refitting and adjustment
1
Removal
1 Disconnect the battery negative (earth) lead
(refer to Chapter 5A, Section 1).
2 Working inside the vehicle, disconnect the
cable from the top of the accelerator pedal,
release the grommet and pull the cable free
from the pedal. Withdraw the cable through
the engine side of the bulkhead.
3 Refer to Section 2 and remove the air
cleaner.
4 Detach the inner cable from the carburettor
linkage.
5 Prise free the retaining clip, detach the
outer cable from the support bracket, and
remove the cable (see illustrations) .
Refitting and adjustment
6To refit the cable, feed the inner cable
through the bulkhead, and reconnect the inner
cable to the accelerator pedal. Note that a
plastic sleeve is supplied with new cables for
the purpose of routing through the bulkhead
panel.
7 Locate the grommet in the bulkhead, then
push the outer cable into it to secure it in the
bulkhead.
8 Lubricate the cable grommet at the
carburettor end with a mild soapy solution, then reconnect the cable to the carburettor.
Locate the outer cable by pulling it towards
the rocker cover.
9
Have an assistant depress the accelerator
pedal fully, and hold it in this position. The
outer cable should be seen to move in its
grommet. Refit the securing clip to the
bracket, then release the accelerator pedal.
10 Depress the accelerator pedal, then
release it and check that the throttle opens
and shuts fully. Further adjust if necessary
before refitting the air cleaner and
reconnecting the battery.
4 Accelerator cable (CTX automatic transmission
models) - adjustment
4
The system for operating the throttle-plate
in the carburettor on CTX automatic
transmission equipped vehicles is completely
different to that employed on manual
transmission vehicles. The cable from the
accelerator pedal leads to a linkage
mechanism which is bolted to the
transmission housing. Two further cables lead
from this linkage mechanism, one of which
operates the throttle-plate in the carburettor. As all three cables have to be adjusted at
the same time, and access to a Ford special
tool is required, it is recommended that a Ford
dealer be entrusted with cable adjustments,
or renewal.
5 Accelerator pedal -
removal and refitting
1
Removal
1 Disconnect the battery negative (earth) lead
(refer to Chapter 5A, Section 1).
2 Peel back the carpet and insulation from
the driver’s footwell to allow access to the
accelerator pedal.
3 Detach the accelerator cable from the pedal
(see Section 3), then release the circlip from
the pivot shaft and remove the accelerator
pedal.
Refitting
4 Refit in the reverse order of removal. On
completion, check the action of the pedal and
the cable to ensure that the throttle has full
unrestricted movement, and fully returns
when released.
5 Reconnect the battery negative lead.
6 Choke cable - removal,
refitting and adjustment
1
Removal
1 Disconnect the battery negative (earth) lead
(refer to Chapter 5A, Section 1).
2 Refer to Section 2 and remove the air
cleaner.
3 Referring to Chapter 10, Section 20, for
further details and illustrations, remove the
choke control knob on the side of the steering
column shroud by pushing in the pin located
on the side of the knob and withdrawing.
4 Detach the steering column lower shroud,
disconnect the multi-plug from the choke
warning light switch/pull control assembly,
and unscrew the collar securing the
switch/pull control assembly to the shroud.
5 Disconnect the choke inner cable from its
location on the carburettor choke linkage,
then release the outer cable retaining clip (see
illustrations) .
6 Push the bulkhead panel grommet through
the bulkhead and remove the cable.
Refitting
7 Route the cable through the bulkhead then
secure the bulkhead panel grommet to its
location.
8 Reconnect the choke inner cable to its
location on the carburettor choke linkage.
9 Refit the choke warning light switch/pull
control assembly to the lower steering column
shroud and secure with the collar, then
reconnect the multi-plug.
10 Refit and secure the lower steering
column shroud, then refit the choke control
knob.
11 Pull the choke control knob to the fully-on
position. Hold the choke in the fully-on
4A•4 Fuel system – carburettor engines
6.5b Choke outer cable retaining clip
released6.5a Disconnect the inner cable from thechoke linkage
3.5b . . . then release from its support bracket3.5a Remove the accelerator outer cablesecuring clip . . .
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This is used to refine the calculations made by
the module, when determining the correct
amount of fuel required to achieve the ideal
air/fuel mixture ratio.A throttle position sensor is mounted on the
end of the throttle valve spindle, to provide
the EEC IV module with a constantly-varying
(analogue) voltage signal corresponding to the
throttle opening. This allows the module to
register the driver’s input when determining
the amount of fuel required by the engine. Road speed is monitored by the vehicle
speed sensor. This component is a Hall-effect
generator, mounted on the transmission’s
speedometer drive. It supplies the EEC IV
module with a series of pulses corresponding
to the vehicle’s road speed, enabling the
module to control features such as the fuel
shut-off on overrun. A manifold absolute pressure sensor
measures inlet manifold vacuum, and supplies
this information to the module for calculation
of engine load at any given throttle position. Where power steering is fitted, a pressure-
operated switch is screwed into the power
steering system’s high-pressure pipe. The
switch sends a signal to the EEC IV module to
reduce engine speed should the power
steering fluid pressure become excessively
high. Certain later engines may be fitted with a
heater in the inlet manifold. This is controlled
by the EEC IV module to ensure that, even
before the effect of the coolant heating
becomes apparent, the manifold is warmed-
up. This prevents fuel droplets condensing in
the manifold, thus improving driveability and
reducing exhaust emissions when the engine
is cold.
The oxygen sensor in the exhaust system
provides the EEC IV module with constant
feedback - “closed-loop” control - which
enables it to adjust the mixture to provide the
best possible conditions for the catalytic
converter to operate.
Precautions
Warning: Petrol is extremely
flammable - great care must be
taken when working on any part
of the fuel system. Do not
smoke or allow any naked flames or
uncovered light bulbs near the work area.
Note that gas powered domestic
appliances with pilot flames, such as
heaters, boilers and tumble dryers, also
present a fire hazard - bear this in mind if
you are working in an area where such
appliances are present. Always keep a
suitable fire extinguisher close to the work
area and familiarise yourself with its
operation before starting work. Wear eye
protection when working on fuel systems
and wash off any fuel spilt on bare skin
immediately with soap and water. Note
that fuel vapour is just as dangerous as
liquid fuel; a vessel that has just been
emptied of liquid fuel will still contain vapour and can be potentially explosive.
Petrol is a highly dangerous and volatile
liquid, and the precautions necessary
when handling it cannot be overstressed.
Many of the operations described in this
Chapter involve the disconnection of fuel
lines, which may cause an amount of fuel
spillage. Before commencing work, refer
to the above Warning and the information
in “Safety first” at the beginning of this
manual. When working with fuel system
components, pay particular attention to
cleanliness - dirt entering the fuel system
may cause blockages which will lead to
poor running.
Note: Residual pressure will remain in the fuel
lines long after the vehicle was last used,
when disconnecting any fuel line, it will be
necessary to depressurise the fuel system as
described in Section 2 .
2 Fuel system-
depressurisation
1
Note: Refer to the warning note in Section 1
before proceeding.
Warning: The following
procedure will merely relieve the
pressure in the fuel system -
remember that fuel will still be present in
the system components, and take
precautions accordingly before
disconnecting any of them.
1 The fuel system referred to in this Chapter
is defined as the fuel tank and tank-mounted
fuel pump/fuel gauge sender unit, the fuel
filter, the fuel injector, fuel pressure regulator,
and the metal pipes and flexible hoses of the
fuel lines between these components. All
these contain fuel, which will be under
pressure while the engine is running and/or
while the ignition is switched on.
2 The pressure will remain for some time after
the ignition has been switched off, and must
be relieved before any of these components is
disturbed for servicing work.
3 The simplest depressurisation method is to
disconnect the fuel pump electrical supply by
removing the fuel pump fuse (No 19) and
starting the engine; allow the engine to idle
until it dies through lack of fuel pressure. Turn
the engine over once or twice on the starter to
ensure that all pressure is released, then
switch off the ignition; do not forget to refit the
fuse when work is complete.
4 Note that, once the fuel system has been
depressurised and drained (even partially), it
will take significantly longer to restart the
engine - perhaps several seconds of cranking
- before the system is refilled and pressure
restored.
3 Fuel lines and fittings -
general information
Note: Refer to the warning note in Section 1
before proceeding.
Disconnecting and connecting
quick-release couplings
1 Quick-release couplings are employed at
many of the unions in the fuel feed and return
lines.
2 Before disconnecting any fuel system
component, relieve the residual pressure in
the system (see Section 2), and equalise tank
pressure by removing the fuel filler cap.
Warning: This procedure will
merely relieve the increased
pressure necessary for the
engine to run - remember that
fuel will still be present in the system
components, and take precautions
accordingly before disconnecting any of
them.
3 Release the protruding locking lugs on each
union, by squeezing them together and
carefully pulling the coupling apart. Use rag to
soak up any spilt fuel. Where the unions are
colour-coded, the pipes cannot be confused.
Where both unions are the same colour, note
carefully which pipe is connected to which,
and ensure that they are correctly
reconnected on refitting.
4 To reconnect one of these couplings, press
them together until the locking lugs snap into
their groove. Switch the ignition on and off
five times to pressurise the system, and check
for any sign of fuel leakage around the
disturbed coupling before attempting to start
the engine.
Checking
5 Checking procedures for the fuel lines are
included in Chapter 1.
Component renewal
6 If any damaged sections are to be renewed,
use original-equipment replacement hoses or
pipes, constructed from exactly the same
material as the section being replaced. Do not
install substitutes constructed from inferior or
inappropriate material; this could cause a fuel
leak or a fire.
7 Before detaching or disconnecting any part
of the fuel system, note the routing of all
hoses and pipes, and the orientation of all
clamps and clips. Replacement sections must
be installed in exactly the same manner.
8 Before disconnecting any part of the fuel
system, be sure to relieve the fuel system
pressure (see Section 2), and equalise tank
pressure by removing the fuel filler cap. Also
disconnect the battery negative (earth) lead -
see Chapter 5A, Section 1. Cover the fitting
being disconnected with a rag, to absorb any
fuel that may spray out.
Fuel system - central fuel injection engines 4B•3
4B
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module from inside the passenger
compartment as its mounting bracket
retaining tags are compressed and released
from the engine compartment. Do not allow
the module to drop into the passenger
compartment as irreparable damage is likely
to result (see illustration) . The module may
be separated from its mounting bracket by
undoing the securing bolts.
38 Refitting is a reversal of the removal
procedure, ensuring that the module
mounting bracket retaining tags are felt to
snap into position
Crankshaft position sensor
39 Refer to Chapter 5B.
Coolant temperature sensor
40Refer to Chapter 3.
Inlet air temperature sensor
41Remove the air cleaner assembly as
described in Section 4.
42 Releasing its clip, unplug the sensor’s
electrical connector, then unscrew the sensor
from the CFi unit (see illustration).
43 Refitting is the reverse of the removal
procedure. Tighten the sensor to the specified
torque wrench setting; if it is overtightened, its
tapered thread may crack the resonator.
Throttle position sensor
44 Remove the air cleaner assembly as
described in Section 4.
45 Releasing its wire clip, unplug the
sensor’s wiring connector. Remove the
retaining screws, and withdraw the unit from
the throttle plate control motor bracket (see
illustration) . Do not force the sensor’s centre
to rotate past its normal operating sweep; the
unit will be seriously damaged.
46 Refitting is the reverse of the removal
procedure, ensuring that the sensor actuating
arm is correctly located.
Vehicle speed sensor
47 The sensor is mounted at the base of the
speedometer drive cable, and is removed with
the speedometer drive pinion. Refer to the
relevant Section of Chapter 7A or B, as
applicable.
Manifold absolute pressure
sensor
48 The sensor is located near the centre of
the engine compartment bulkhead.
49 Disconnect the wiring multi-plug, and
detach the vacuum hose from the base of the
sensor (see illustration) .
50 Undo the two retaining screws, and
withdraw the sensor from its location. 51
Refitting is the reverse of the removal
procedure.
Power steering pressure switch
52 Releasing its clip, unplug the switch’s
electrical connector, then unscrew the switch
from the power steering high pressure pipe.
Place a wad of rag underneath, to catch any
spilt fluid. If a sealing washer is fitted, renew it
if it is worn or damaged.
53 Refitting is the reverse of the removal
procedure; tighten the switch securely, then
top-up the fluid reservoir (see “Weekly
Checks” ) to replace any fluid lost from the
system, and bleed out any trapped air (see
Chapter 10).
Oxygen sensor
Note: The sensor is delicate, and will not work
if it is dropped or knocked, if its power supply
is disrupted, or if any cleaning materials are
used on it.
54 Release the sensor’s electrical connector
from its bracket and unplug it to disconnect
the sensor (see illustration) .
55 Raise and support the front of the vehicle
if required to remove the sensor from
underneath (“see Jacking and vehicle
support” ). Remove the sensor heat shield then
unscrew the sensor from the exhaust system
front downpipe; collect the sealing washer
(where fitted).
56 On refitting, clean the sealing washer
(where fitted) and renew it if it is damaged or
4B•8 Fuel system - central fuel injection engines
14.54 Oxygen sensor (A) (shown with its
heatshield removed), and its multi-plug (B)
14.49 Manifold absolute pressure sensor location
A Securing screws B Multi-plug C Vacuum hose\
Arrows indicate ignition module retaining screws
14.45 Throttle position sensor retainingscrews (arrowed) (shown with throttle plate control motor removed)14.42 Disconnecting the intake airtemperature sensor multi-plug
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Engine temperature information is supplied
by the coolant temperature sensor. This
component is an NTC (Negative Temperature
Coefficient) thermistor - that is, a semi-
conductor whose electrical resistance
decreases as its temperature increases. It
provides the EEC IV module with a constantly-
varying (analogue) voltage signal, corre-
sponding to the temperature of the engine
coolant. This is used to refine the calculations
made by the module, when determining the
correct amount of fuel required to achieve the
ideal air/fuel mixture ratio. Inlet air temperature information is supplied
by the inlet air temperature sensor. This
component is also an NTC thermistor - see the
previous paragraph - providing the module with
a signal corresponding to the temperature of air
passing into the engine. This is used to refine
the calculations made by the module, when
determining the correct amount of fuel required
to achieve the ideal air/fuel mixture ratio. A throttle position sensor is mounted on the
end of the throttle valve spindle, to provide
the EEC IV module with a constantly-varying
(analogue) voltage signal corresponding to the
throttle opening. This allows the module to
register the driver’s input when determining
the amount of fuel required by the engine. Road speed is monitored by the vehicle
speed sensor. This component is a Hall-effect
generator, mounted on the transmission’s
speedometer drive. It supplies the module with a
series of pulses corresponding to the vehicle’s
road speed, enabling the module to control
features such as the fuel shut-off on overrun. A manifold absolute pressure sensor
measures inlet manifold vacuum, and supplies
this information to the EEC IV module for
calculation of engine load at any given throttle
position. Where power steering is fitted, a pressure-
operated switch is screwed into the power
steering system’s high-pressure pipe. The
switch sends a signal to the EEC IV module to
reduce engine speed should the power steering
fluid pressure become excessively high. On models with a catalytic converter, the
oxygen sensor in the exhaust system provides
the EEC IV module with constant feedback -
“closed-loop” control - which enables it to
adjust the mixture to provide the best possible
conditions for the catalytic converter to operate. On turbocharged engines, control of the
turbocharger boost pressure is also governed
by the EEC IV module, acting through the
boost control valve. This allows inlet manifold
depression to be applied to the turbocharger
wastegate control. The turbocharger consists of a turbine that
is driven by the exhaust gases, to suck air
through the air filter and to compress it into the
engine. An air-cooled intercooler, mounted
next to the radiator, cools the inlet air (heated
by its passage through the turbocharger); this
increases the density of the compressed
fuel/air mixture entering the engine, thus
improving the engine’s power output.Precautions
Warning: Petrol is extremely
flammable - great care must be
taken when working on any part
of the fuel system. Do not
smoke or allow any naked flames or
uncovered light bulbs near the work area.
Note that gas powered domestic
appliances with pilot flames, such as
heaters, boilers and tumble dryers, also
present a fire hazard - bear this in mind if
you are working in an area where such
appliances are present. Always keep a
suitable fire extinguisher close to the work
area and familiarise yourself with its
operation before starting work. Wear eye
protection when working on fuel systems
and wash off any fuel spilt on bare skin
immediately with soap and water. Note
that fuel vapour is just as dangerous as
liquid fuel; a vessel that has just been
emptied of liquid fuel will still contain
vapour and can be potentially explosive.
Petrol is a highly dangerous and volatile
liquid, and the precautions necessary
when handling it cannot be overstressed. Many of the operations described in this
Chapter involve the disconnection of fuel
lines, which may cause an amount of fuel
spillage. Before commencing work, refer
to the above Warning and the information
in “Safety first” at the beginning of this
manual. When working with fuel system
components, pay particular attention to
cleanliness - dirt entering the fuel system
may cause blockages which will lead to
poor running.
Note: Residual pressure will remain in the fuel
lines long after the vehicle was last used,
when disconnecting any fuel line, it will be
necessary to depressurise the fuel system as
described in Section 2 .
Note: Refer to Section 16 for specific
precautions relating to turbocharged engines.
2 Fuel system -
depressurisation
1
Refer to Part B, Section 2.
3 Fuel lines and fittings -
general information
Refer to Part B, Section 3.
4 Air cleaner assembly and air inlet components - removal
and refitting
1
Note: Air cleaner element renewal and air
cleaner temperature control system checks
(where applicable) are described in Chapter 1.
Air cleaner assembly
1 Disconnect the battery negative (earth) lead
(refer to Chapter 5A, Section 1).
2 If the idle speed control valve is mounted
on the air cleaner, disconnect the multi-plug
and the air bypass hose from the valve.
3 Disconnect the flexible hose between the
air cleaner lid and the air inlet duct or
turbocharger air inlet.
4 Disconnect the crankcase breather hose
from the front of the air cleaner housing.
5 Unclip and remove the air cleaner lid, then
withdraw the element.
6 Remove the two bolts securing the forward
end of the air cleaner housing, free the
rearward end of the housing from its location
and carefully withdraw from the vehicle (see
illustration) .
7 Refitting is a reversal of the removal
procedure.
Air inlet components
8 Disconnect the battery negative (earth) lead
(refer to Chapter 5A, Section 1).
9 If the idle speed control valve is mounted
on the air cleaner, disconnect the multi-plug
and the air bypass hose from the valve (see
illustration) .
10 Disconnect the HT leads from the spark
plugs, labelling them if necessary to avoid
confusion on refitting.
Fuel system - electronic fuel injection engines 4C•3
4.9 General view of the air inlet
components on non-Turbo models
A Air inlet duct
B Air inlet duct securing bolts
C Spark plug HT lead connectors
D Air cleaner lid
E Idle speed control valve multi-plug
F Air bypass hose
4.6 Air cleaner housing attachments A Bolts B Grommet
4C
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Crankshaft position sensor
40Refer to Chapter 5B.
Coolant temperature sensor
41Refer to Chapter 3.
Inlet air temperature sensor
42Remove the air inlet components as
described in Section 4.
43 Releasing its clip, unplug the sensor’s
electrical connector, then unscrew the sensor
from the inlet manifold (see illustration).
44 Refitting is the reverse of the removal
procedure.
Throttle position sensor
45 Remove the air inlet components as
described in Section 4.
46 Releasing its wire clip, unplug the
sensor’s electrical connector. Remove the
retaining screws, and withdraw the unit from
the throttle housing (see illustration). Do not
force the sensor’s centre to rotate past its
normal operating sweep; the unit will be
seriously damaged.
47 Refitting is the reverse of the removal
procedure, noting the following points (see
illustration) :
a) Ensure that the potentiometer is correctly
orientated, by locating its centre on the D-
shaped throttle shaft (throttle closed), and aligning the potentiometer body so that
the bolts pass easily into the throttle
housing.
b) Tighten the screws evenly and securely
(but do not overtighten them, or the
potentiometer body will be cracked).
Vehicle speed sensor
48 The sensor is mounted at the base of the
speedometer drive cable, and is removed with
the speedometer drive pinion. Refer to the
relevant Section of Chapter 7A or B, as
applicable.
Manifold absolute pressure
sensor
49 The sensor is located near the centre of
the engine compartment bulkhead.
50 Disconnect the wiring multi-plug, and
detach the vacuum hose from the base of the
sensor.
51 Undo the two retaining screws, and
withdraw the sensor from its location.
52 Refitting is the reverse of the removal
procedure.
Power steering pressure switch
53 Releasing its clip, unplug the switch’s
electrical connector, then unscrew the switch
from the power steering high pressure pipe.
Place a wad of rag underneath, to catch any spilt fluid. If a sealing washer is fitted, renew it
if it is worn or damaged.
54
Refitting is the reverse of the removal
procedure; tighten the switch securely, then
top-up the fluid reservoir (see “Weekly
Checks” ) to replace any fluid lost from the
system, and bleed out any trapped air (see
Chapter 10).
Oxygen sensor
Note: The sensor is delicate, and will not work
if it is dropped or knocked, if its power supply
is disrupted, or if any cleaning materials are
used on it.
55 Release the sensor’s wiring multi-plug
from its bracket below the starter motor, and
unplug it to disconnect the sensor.
56 Raise and support the front of the vehicle
if required to remove the sensor from
underneath (“see Jacking and vehicle
support” ). Remove the sensor heat shields
then unscrew the sensor from the exhaust
system front downpipe; collect the sealing
washer (where fitted).
57 On refitting, clean the sealing washer
(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. Reconnect
the wiring, and refit the connector plug.
Fuel mixture/CO% adjustment
potentiometer
58 The fuel mixture/CO% adjustment
potentiometer is located on the engine
compartment bulkhead below the ignition
module.
59 Disconnect the battery negative (earth)
lead (refer to Chapter 5A, Section 1).
60 Disconnect the potentiometer’s wiring
multiplug (see illustration) .
61 Unscrew the retaining screw and remove
the potentiometer from the bulkhead.
62 Refitting is the reverse of the removal
procedure.
Fuel system - electronic fuel injection engines 4C•7
14.46 Disconnect the multi-plug from the throttle position sensor. Sensor retaining screws (arrowed)14.43 Disconnecting the intake airtemperature sensor multi-plug
14.60 Fuel mixture/CO% adjustment potentiometer
A Securing screw B Multi-plug14.47 General view of the throttle position sensor and its “D” shaped throttle spindle location (arrowed)
4C
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1 General information andprecautions
General information
The fuel system consists of a fuel tank
(mounted under the body, beneath the rear
seats), fuel hoses, an electric fuel pump
mounted in the fuel tank, and a sequential
electronic fuel injection system.
The electric fuel pump supplies fuel under
pressure to the fuel rail, which distributes fuel
evenly to all injectors. A pressure regulator
controls the system pressure in relation to
inlet tract depression. From the fuel rail, fuel is
injected into the inlet ports, just above the
inlet valves, by four fuel injectors. The system
also includes features such as the flushing of
fresh (ie, cold) fuel around each injector on
start-up, thus improving hot starts. The amount of fuel supplied by the injectors
is precisely controlled by the EEC IV engine
management module. The module uses the
signals derived from the crankshaft position
sensor and the camshaft position sensor, to
trigger each injector separately in cylinder
firing order (sequential injection), with benefits
in terms of better fuel economy and lower
exhaust emissions. The EEC IV module is the heart of the entire
engine management system, controlling the
fuel injection, ignition and emissions control
systems. The module receives information
from various sensors which is then computed
and compared with pre-set values stored in
it’s memory, to determine the required period
of injection. Information on crankshaft position and
engine speed is generated by a crankshaft
position sensor. The inductive head of the
sensor runs just above the engine flywheel
and scans a series of 36 protrusions on the
flywheel periphery. As the crankshaft rotates,
the sensor transmits a pulse to the system’s
ignition module every time a protrusion
passes it. There is one missing protrusion in
the flywheel periphery at a point
corresponding to 90° BTDC. The ignition
module recognises the absence of a pulse
from the crankshaft position sensor at this
point to establish a reference mark for
crankshaft position. Similarly, the time interval
between absent pulses is used to determine
engine speed. This information is then fed to
the EEC IV module for further processing. The camshaft position sensor is located in
the cylinder head so that it registers with a
lobe on the camshaft. The camshaft position
sensor functions in the same way as the
crankshaft position sensor, producing a series
of pulses; this gives the EEC IV module a
reference point, to enable it to determine the
firing order, and operate the injectors in the
appropriate sequence. The mass air flow sensor is based on a “hot-
wire” system, sending the EEC IV module a constantly-varying (analogue) voltage signal
corresponding to the mass of air passing into
the engine. Since air mass varies with
temperature (cold air being denser than warm),
measuring air mass provides the module with
a very accurate means of determining the
correct amount of fuel required to achieve the
ideal air/fuel mixture ratio.
Engine temperature information is supplied by
the coolant temperature sensor. This
component is an NTC (Negative Temperature
Coefficient) thermistor - that is, a semi-
conductor whose electrical resistance
decreases as its temperature increases. It
provides the EEC IV module with a constantly-
varying (analogue) voltage signal, corresponding
to the temperature of the engine coolant. This is
used to refine the calculations made by the
module, when determining the correct amount
of fuel required to achieve the ideal air/fuel
mixture ratio. Inlet air temperature information is supplied
by the inlet air temperature sensor. This
component is also an NTC thermistor - see
the previous paragraph - providing the
module with a signal corresponding to the
temperature of air passing into the engine.
This is used to refine the calculations made by
the module, when determining the correct
amount of fuel required to achieve the ideal
air/fuel mixture ratio. A throttle position sensor is mounted on the
end of the throttle valve spindle, to provide
the EEC IV module with a constantly-varying
(analogue) voltage signal corresponding to the
throttle opening. This allows the module to
register the driver’s input when determining
the amount of fuel required by the engine.
Road speed is monitored by the vehicle
speed sensor. This component is a Hall-effect
generator, mounted on the transmission’s
speedometer drive. It supplies the module
with a series of pulses corresponding to the
vehicle’s road speed, enabling the module to
control features such as the fuel shut-off on
overrun.
Where power steering is fitted, a pressure-
operated switch is screwed into the power
steering system’s high-pressure pipe. The
switch sends a signal to the EEC IV module to
reduce engine speed should the power
steering fluid pressure become excessively
high.
The oxygen sensor in the exhaust system
provides the module with constant feedback -
“closed-loop” control - which enables it to
adjust the mixture to provide the best possible
conditions for the catalytic converter to
operate. The air inlet side of the system consists of
an air cleaner housing, the mass air flow
sensor, an inlet hose and duct, and a throttle
housing. The throttle valve inside the throttle housing
is controlled by the driver, through the
accelerator pedal. As the valve opens, the
amount of air that can pass through the
system increases. As the throttle valve opens further, the mass air flow sensor signal alters,
and the EEC IV module opens each injector
for a longer duration, to increase the amount
of fuel delivered to the inlet ports.
Both the idle speed and mixture are under
the control of the EEC IV module, and cannot
be adjusted. Not only can they not be
adjusted, they cannot even be checked,
except with the use of special Ford diagnostic
equipment.
Precautions
Warning: Petrol is extremely
flammable - great care must be
taken when working on any part
of the fuel system. Do not
smoke or allow any naked flames or
uncovered light bulbs near the work area.
Note that gas powered domestic
appliances with pilot flames, such as
heaters, boilers and tumble dryers, also
present a fire hazard - bear this in mind if
you are working in an area where such
appliances are present. Always keep a
suitable fire extinguisher close to the work
area and familiarise yourself with its
operation before starting work. Wear eye
protection when working on fuel systems
and wash off any fuel spilt on bare skin
immediately with soap and water. Note
that fuel vapour is just as dangerous as
liquid fuel; a vessel that has just been
emptied of liquid fuel will still contain
vapour and can be potentially explosive.
Petrol is a highly dangerous and volatile
liquid, and the precautions necessary
when handling it cannot be overstressed. Many of the operations described in this
Chapter involve the disconnection of fuel
lines, which may cause an amount of fuel
spillage. Before commencing work, refer
to the above Warning and the information
in “Safety first” at the beginning of this
manual. When working with fuel system
components, pay particular attention to
cleanliness - dirt entering the fuel system
may cause blockages which will lead to
poor running.
Note: Residual pressure will remain in the fuel
lines long after the vehicle was last used,
when disconnecting any fuel line, it will be
necessary to depressurise the fuel system as
described in Section 2 .
2 Fuel system-
depressurisation
1
Refer to Part B, Section 2.
3 Fuel lines and fittings -
general information
Refer to Part B, Section 3.
4D•2 Fuel system - sequential electronic fuel injection engines
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