Ford Fiesta (1989-1995). Instruction - part 33

Fuel tank - removal,
inspection and refitting

Proceed as described in Part A, Section 8,

but before disconnecting the battery, relieve
the residual pressure in the fuel system (see
Section 2), and equalise tank pressure by
removing the fuel filler cap.

Fuel pump/fuel gauge
sender unit - removal and
refitting

Refer to Part B, Section 9.

10 Fuel tank ventilation tube -

removal and refitting

Refer to Part A, Section 10, but note that on

models with evaporative emission control, the
ventilation tube connects to the combined
roll-over/anti-trickle-fill valve assembly but,
instead of venting to atmosphere, a further
tube runs the length of the vehicle to a carbon
canister in the front right-hand corner of the
engine compartment.

Further information on the evaporative

emission control system is contained in Part E
of this Chapter.

11 Fuel tank filler pipe -

removal and refitting

Refer to Part A, Section 11.

12 Fuel cut-off switch -

removal and refitting

Refer to Part B, Section 12.

13 Fuel injection system -

checking

Refer to Part B, Section 13

14 Fuel injection system

components - removal and
refitting

Note: Refer to the warning note in Section 1
before proceeding.

Fuel rail and injectors

Note: For simplicity, and to ensure that the
necessary absolute cleanliness on reassembly,
the following procedure describes the removal
of the fuel rail assembly, complete with the
injectors and pressure regulator, so that
the injectors can be serviced individually on a

clean work surface. It is also possible to remove
and refit an individual injector, once the fuel
system has been depressurised and the battery
has been disconnected. If this approach is
followed, read through the complete
procedure, and work as described in the
relevant paragraphs, depending on the amount
of preliminary dismantling required. Be careful
not to allow any dirt to enter the system.
1 Relieve the residual pressure in the fuel
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.
2 Disconnect the battery negative (earth) lead
(refer to Chapter 5A, Section 1).
3 Disconnect the HT lead connectors from the
spark plugs, and release the leads from their
locating grooves in the air inlet duct. Position
them out of the way. On Turbo models, undo the
two screws and remove the HT lead bracket.
4 Remove the air inlet components as
described in Section 4.
5 Unscrew the retaining nuts and the bolt,
and detach the accelerator cable support
bracket at the throttle housing.
6 Disconnect the wiring connector from the
throttle position sensor.
7 Unscrew the four retaining bolts, and
remove the throttle housing and its mating
face gasket (see illustration).
8 Disconnect the wiring multi-plug from the
engine coolant temperature sensor and the
inlet air temperature sensor.
9 Disconnect the wiring multi-plugs from the
fuel injectors, then undo the two retaining
bolts and detach the wiring harness from the
fuel rail (see illustrations).
10 Unscrew the fuel supply pipe at the fuel
rail. Plug the rail and pipe, to prevent further
fuel spillage and the possible ingress of dirt.
11 Disconnect the fuel return and vacuum
pipes from the pressure regulator, and catch
any fuel spillage in a clean cloth.
12 Unscrew the fuel rail securing bolts, and
carefully withdraw the rail (complete with
injectors) from the engine (see illustrations).

Fuel system - electronic fuel injection engines 4C•5

14.9b . . . unbolt the wiring harness . . .

14.9a Disconnect the wiring multi-plug

from each injector . . .

14.7 Throttle housing retaining bolt

locations (arrowed)

1595Ford Fiesta Remake

14.12a Remove the fuel rail retaining

bolts . . .

14.9c . . . and remove the complete

harness

13 Detach the fuel injectors from the fuel rail,
then remove the upper and lower seal from
each injector (see illustration). All seals must
be renewed (even if only one injector is to be
renewed).
14 Prior to refitting the injectors, ensure that
all mating surfaces are perfectly clean.
Lubricate the new injector seals with clean
engine oil to ease their assembly to the
injectors.
15 Refitting is a reversal of the removal
procedure. Refer to the Specifications at the
start of this Chapter for the tightening torques.
When refitting the fuel rail, ensure that the
injectors are correctly located. Ensure that the
mating surfaces of the throttle housing are
perfectly clean before assembling.
16 On completion, restart the engine and
check the various fuel connections for any
signs of leaks.

Fuel pressure regulator

17 Relieve the residual pressure in the fuel
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.
18 Disconnect the battery negative (earth)
lead (refer to Chapter 5A, Section 1).

19 Release the fuel return pipe securing clip,
and detach the pipe from the regulator.
20 Pull free the vacuum pipe from the
regulator connector (see illustration).
21 Unscrew the two retaining bolts and
remove the regulator. Remove the old sealing
ring for renewal.
22 Refit in the reverse order of removal.
Lubricate the new seal ring with clean engine oil
to ease assembly. When the regulator is refitted
and the fuel and vacuum lines are reconnected,
turn the ignition on and off five times (without
cranking the engine) and check for any sign of
fuel leaks before restarting the engine.

Idle speed control valve

Note: The idle speed control valve may be
mounted on the air cleaner, on the engine
compartment bulkhead, or on the side of the
inlet manifold according to valve make and
year of manufacture. Valves manufactured by
Weber are mounted on the air cleaner and
require periodic maintenance (see Chapter 1).
Bulkhead and inlet manifold mounted valves
are manufactured by Hitachi and are
maintenance free.
23 Disconnect the battery negative (earth)
lead (refer to Chapter 5A, Section 1).
24 Disconnect the valve’s wiring multiplug
(see illustration).
25 Where applicable disconnect the air
hose(s) from the valve.
26 Undo the two or four bolts (according to
type), and remove the valve from the air
cleaner, bulkhead or inlet manifold.

27 Refitting is a reversal of the removal
procedure. Ensure that the mating faces are
clean before reassembling.
28 When the valve is refitted, restart the
engine and check that there are no induction
leaks. Run the engine until its normal
operating temperature is reached, and check
that the idle speed is stable. Stop the engine,
connect up a tachometer in accordance with
its maker’s instructions, then restart the
engine and check that the idle speed is as
specified with all electrical items (lights, heater
blower motor, etc) switched off, then on. The
idle speed should remain the same. Switch off
the electrical items, turn the engine off and
detach the tachometer to complete the test.

Throttle housing

29 Disconnect the battery negative (earth)
lead (refer to Chapter 5A, Section 1).
30 Disconnect the ignition HT lead
connectors from the spark plugs, and release
the leads from their locating grooves in the air
inlet duct. Position them out of the way.
31 Remove the air inlet components as
described in Section 4.
32 Unscrew the retaining nuts and the bolt,
and detach the accelerator cable support
bracket at the throttle housing.
33 Disconnect the wiring connector from the
throttle position sensor.
34 Unscrew the four retaining bolts, and
remove the throttle housing and its mating
face gasket (see illustration 14.7).
35 Refit in the reverse order of removal.
Check that the mating faces are clean, and fit
a new gasket.

EEC IV engine management
module

Note: The module is fragile. Take care not to
drop it, or subject it to any other kind of
impact. Do not subject it to extremes of
temperature, or allow it to get wet. Refer to
Part B, Section 14 for illustrations of the
following procedure.
36 Disconnect the battery negative (earth)
lead (refer to Chapter 5A, Section 1).
37 Unscrew and remove the two nuts
securing the module cover in the engine
compartment, then carefully draw the cover
away from its location. Unscrew the module
multi-plug retaining bolt and disconnect
the multi-plug from the module.
38 The aid of an assistant will be required at
this stage, to support and withdraw the
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. The
module may be separated from its mounting
bracket by undoing the securing bolts.
39 Refitting is a reversal of the removal
procedure, ensuring that the module
mounting bracket retaining tags are felt to
snap into position

4C•6 Fuel system - electronic fuel injection engines

14.24 Disconnect the multi-plug from the

idle speed control valve. Upper valve

retaining bolt (arrowed)

14.20 Fuel pressure regulator showing

vacuum pipe (A) and fuel return pipe

connection (B)

14.13 Remove the seals from the injectors

14.12b . . . and withdraw the fuel rail and

injectors

1595Ford Fiesta Remake

Crankshaft position sensor

40 Refer to Chapter 5B.

Coolant temperature sensor

41 Refer to Chapter 3.

Inlet air temperature sensor

42 Remove 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 air

temperature sensor multi-plug

14.60 Fuel mixture/CO% adjustment potentiometer

A Securing screw B Multi-plug

14.47 General view of the throttle position sensor and its

“D” shaped throttle spindle location (arrowed)

1595Ford Fiesta Remake

15 Inlet manifold -

removal and refitting

Note: Refer to the warning note in Section 1
before proceeding.

Removal

1 The inlet manifold is a two-piece assembly
comprising an upper and lower section bolted
together (see illustration).
2 Drain the cooling system with reference to
Chapter 1.
3 Depressurise the fuel system as described
in Section 2.
4 Disconnect the battery negative (earth) lead
(refer to Chapter 5A, Section 1).
5 Remove the air inlet components (Section
4) and disconnect the accelerator cable from
the throttle linkage (Section 5).
6 Remove the fuel injectors and fuel rail as
described in Section 14.
7 Noting their locations, disconnect the
coolant, vacuum and breather hoses from the
manifold.
8 Disconnect the wiring multi-plugs from the
engine sensors at the inlet manifold.
9 Undo the retaining bolts, and withdraw the
manifold from the cylinder head. Note the
location of the engine lifting bracket and earth
lead, where fitted. Remove the gasket.
10 With the manifold removed, clean all
traces of the old gasket from the mating

surfaces of the manifold and the cylinder
head.

Refitting

11 Refitting is the reversal of removal. Use a
new gasket, and tighten the retaining bolts to
the specified torque (see illustration).
Refit the remainder of the components with
reference to the appropriate Chapters of this
instruction. Refill the cooling system as
described in Chapter 1 on completion.

16 Turbocharger - general

information and precautions

General information

1 A water-cooled turbocharger is used on all
Turbo models covered by this instruction. The
turbocharger increases the efficiency of the
engine by raising the pressure in the inlet
manifold above atmospheric pressure.
Instead of the air/fuel mixture being simply
sucked into the cylinders it is actively forced
in.
2 Energy for the operation of the
turbocharger comes from the exhaust gas.
The gas flows through a specially-shaped
housing (the turbine housing) and in so doing
spins the turbine wheel. The turbine wheel is
attached to a shaft, at the other end of which
is another vaned wheel known as the

compressor wheel. The compressor wheel
spins in its own housing and compresses the
inducted air on the way to the inlet manifold.
3 After leaving the turbocharger, the
compressed air passes through an
intercooler, which is an air-to-air heat
exchanger mounted with the radiator. Here
the air gives up heat which it acquired when
being compressed. This temperature
reduction improves engine efficiency and
reduces the risk of detonation.
4 Boost pressure (the pressure in the inlet
manifold) is limited by the turbocharger
wastegate control, which diverts the exhaust
gas away from the turbine wheel in response
to the boost control valve. The valve is
controlled by the EEC IV engine management
module.
5 The turbo shaft is pressure-lubricated by
means of a feed pipe from the engine’s main oil
gallery. The shaft “floats” on a cushion of oil. A
drain pipe returns the oil to the sump.
6 Water cooling reduces the operating
temperature of the turbocharger, and in
particular, the shaft bearings. Water continues
to circulate by convection after the engine has
stopped, so cooling the unit if it is hot after a
long run.

Precautions

7 The turbocharger operates at extremely
high speeds and temperatures. Certain
precautions must be observed to avoid
premature failure of the turbo or injury to the
operator.

a) Do not operate the turbo with any parts

exposed. Foreign objects falling onto the
rotating vanes could cause extensive
damage and (if ejected) personal injury.

b) Do not race the engine immediately after

start-up, especially if it is cold. Give the oil
a few seconds to circulate.

c) Always allow the engine to return to idle

speed before switching it off - do not blip
the throttle and switch off, as this will
leave the turbo spinning without
lubrication.

d) Allow the engine to idle for several

minutes before switching off after a high-
speed run.

e) Observe the recommended intervals for

oil and filter changing, and use a
reputable oil of the specified quality.
Neglect of oil changing, or use of inferior
oil, can cause carbon formation on the
turbo shaft and subsequent failure.

17 Intercooler -

removal and refitting

Removal

1 Disconnect the battery negative (earth) lead
(refer to Chapter 5A, Section 1).
2 Remove the flexible hose connecting the
intercooler to the air inlet duct, then the pipe

4C•8 Fuel system - electronic fuel injection engines

15.1 Exploded view of the inlet manifold arrangement

1595Ford Fiesta Remake

Content .. 31 32 33 34 ..