1990 FORD SIERRA torque

Torque wrench settingsNmlbf ft
2.0 litre SOHC models
Refer to Chapter 4
, PartA Specifications for items not listed here
Fuel pressure regulator fuel feed union nut . . . . . . . . . . . . . . . . . . . . . .15 to 2011 to 15
Fuel pressure regulator securing nut . . . . . . . . . . . . . . . . . . . . . . . . . . .20 to 2515 to 18
Fuel rail securing bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8 to 106 to 7
Idle speed control valve nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8 to 106 to 7
2.0 litre DOHC models
Inlet manifold nuts and bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20 to 2415 to 18
Exhaust manifold nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21 to 2515 to 18
Exhaust gas oxygen sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50 to 7037 to 52
Throttle body bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9 to 117 to 8
Fuel rail bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21 to 2615 to 19
Idle speed control valve bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9 to 117 to 8
Fuel pressure regulator bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9 to 127 to 9
Fuel filter unions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14 to 2010 to 15
1.6 and 1.8 litre (R6A type) CVH models
Inlet manifold nuts and bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16 to 2012 to 15
Exhaust manifold nuts:
1.6 litre . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14 to 1710 to 13
1.8 litre . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21 to 2715 to 20
Exhaust downpipe-to-manifold nuts . . . . . . . . . . . . . . . . . . . . . . . . . . .35 to 4026 to 30
CFI unit bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9 to 117 to 8
Exhaust gas oxygen sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50 to 7037 to 52
EGR valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20 to 3015 to 22
Fuel filter unions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14 to 2010 to 15
Pulse-air tube unions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29 to 3521 to 26
General information
2.0 litre SOHC models
The fuel injection system fitted to these
models is of the Bosch L-Jetronic type. The
system is under the overall control of an EEC
IV engine management system which also
controls the ignition timing.
Fuel is supplied from the rear-mounted fuel
tank by an electric fuel pump mounted next to
the tank, via a pressure regulator, to the fuel
rail. The fuel rail acts as a reservoir for the four
fuel injectors, which inject fuel into the cylinder
inlet tracts, upstream of the inlet valves. The
fuel injectors receive an electrical pulse once
per crankshaft revolution, which operates all
four injectors simultaneously. The duration of
the electrical pulse determines the quantity of
fuel injected, and pulse duration is computed
by the EEC IV module on the basis of
information received from the various sensors.
Inducted air passes from the air cleaner
through a vane type airflow meter before
passing to the cylinder inlet tracts via the
throttle valve. A flap in the vane airflow meter
is deflected in proportion to the airflow; this
deflection is converted into an electrical signal
and passed to the EEC IV module. An
adjustable air bypass channel provides the
means of idle mixture adjustment.
A throttle position sensor enables the EEC IV
module to compute not only throttle position,
but also its rate of change. Extra fuel can thus
be provided for acceleration when the throttle
is opened suddenly. Information from the
throttle position sensor is also used to cut off
fuel on the overrun, thus improving fueleconomy and reducing exhaust gas emissions.
Idle speed is controlled by a variable orifice
solenoid valve which regulates the amount of
air bypassing the throttle valve. The valve is
controlled by the EEC IV module; there is no
provision for adjustment of the idle speed.
Additional sensors inform the EEC IV
module of engine coolant and air temperature.
On models fitted with automatic transmission,
a sensor registers the change from “P” or “N”
to a drive position, and causes the idle speed
to be adjusted accordingly to compensate for
the additional load. Similarly on models fitted
with air conditioning, a sensor registers when
the compressor clutch is in operation.
A “limited operation strategy” (LOS) means
that the vehicle is still driveable, albeit at
reduced power and efficiency, in the event of
a failure in the EEC IV module or its sensors.
A fuel filter is incorporated in the fuel supply
line to ensure that the fuel supplied to the
injectors is clean.
On models produced from mid-1986
onwards, a fuel pump inertia cut-off switch is
fitted. This switch breaks the electrical circuit
to the fuel pump in the event of an accident or
similar impact, cutting off the fuel supply to
the engine.
2.0 litre DOHC models
The fuel injection system fitted to these
models is under the overall control of an EEC
IV engine management system which also
controls the ignition timing.
Fuel is supplied from the rear-mounted fuel
tank by an electric fuel pump, which is integral
with the fuel level sender unit mounted inside
the fuel tank. Fuel passes via a fuel filter and a
pressure regulator to the fuel rail. The fuel rail
acts as a reservoir for the four fuel injectors,
which inject fuel into the cylinder inlet tracts,
upstream of the inlet valves. The fuel injectorsare operated in pairs by electrical pulses
supplied by the EEC IV module, and fuel is
injected by one pair of injectors every half-
revolution of the crankshaft. The duration of
each electrical pulse determines the quantity of
fuel injected, and pulse duration is computed
by the EEC IV module on the basis of
information received from the various sensors.
Inducted air passes through the air cleaner,
and through a plenum chamber, before
passing on to the cylinder inlet tracts via the
throttle valve and inlet manifold. The volume
of air entering the engine is calculated by the
EEC IV module from information supplied by
various sensors. These sensors include an air
charge temperature sensor mounted in the
inlet manifold, which measures the
temperature of the air entering the engine; a
manifold absolute pressure (MAP) sensor,
which measures the pressure of the air
entering the engine; a throttle position sensor;
and a crankshaft speed/position sensor,
which supplies information on engine speed
and provides a timing reference.
Additional sensors inform the EEC IV
module of fuel temperature, engine coolant
temperature, and vehicle speed (from a
gearbox-mounted sensor).
Idle speed is controlled by a variable-orifice
solenoid valve, which regulates the amount of
air bypassing the throttle valve. The valve is
controlled by the EEC IV module; there is no
provision for direct adjustment of the idle
speed.
On models without a catalytic converter,
idle mixture adjustment is by means of a
potentiometer connected directly to the EEC
IV module. On models with a catalytic
converter, an exhaust gas oxygen (HEGO)
sensor enables the EEC IV module to control
the fuel/air mixture to suit the operating
parameters of the catalytic converter; no
1General information and
precautions
4B•2Fuel and exhaust systems - fuel injection

together and using them to unscrew the stud
(see illustration). Alternatively, the distributor
can be removed, although this is not
recommended unless absolutely essential.
Recover the gasket. Note that an earth strap
may be located on one of the manifold
securing bolts or studs; where applicable,
note its location as an aid to refitting.
14With the manifold removed, the various
fuel injection system components can be
separated from the manifold with reference to
the relevant Sections of this Chapter.
15Refitting is a reversal of removal, bearing
in mind the following points.
16Renew the gasket, and apply a bead of
sealant at least 5.0 mm (0.2 in) wide around
the central coolant aperture on both sides of
the gasket. Ensure that all mating faces are
clean.17Tighten the manifold securing nuts and
bolts progressively to the specified torque,
where applicable ensuring that the earth strap
is in position.
18Make sure that all hoses, cables, wires
and leads are correctly reconnected. When
reconnecting the air inlet hose, make sure that
the hose clips are correctly aligned, see
illustration, Section 15.
19On completion, refill the cooling system,
adjust the throttle cable and check and if
necessary adjust the idle mixture.
2.0 litre DOHC models
Note:New fuel injector seals must be used on
refitting.
20Disconnect the battery negative lead.
21Partially drain the cooling system.
22Disconnect the coolant hoses from the
thermostat housing and the inlet manifold.
23Disconnect the air inlet hose from the
front of the inlet manifold.
24Disconnect the breather hoses and the
vacuum hoses from the inlet manifold noting
their locations when disconnecting the brake
servo vacuum hose.
25Disconnect the throttle cable from the
throttle linkage (see illustrations).
26Disconnect the HT leads from the spark
plugs, noting their locations to aid refitting,
and move them to one side.
27Disconnect the wiring from the cooling fan
switch, the engine coolant temperature
sensor, and the temperature gauge sender.
28Release the throttle position sensor wiring
connector from the clip under the throttle body,
and separate the two halves of the connector.
29Remove the fuel injectors.
30Check that all relevant wiring, hoses and
pipes have been disconnected, to facilitate
removal of the manifold.
31Unscrew the ten bolts and two nuts
securing the inlet manifold to the cylinder
head, and carefully withdraw the manifold.
Recover the gasket.
32Recover the two plastic spark plug
spacers from the recesses in the cylinder
head (see illustration).
33If desired, the manifold can be dismantled
with reference to the relevant paragraphs of
this Chapter.
34Refitting is a reversal of removal, bearing
in mind the following points.35Ensure that the spark plug spacers are in
position in the cylinder head recesses before
refitting the manifold.
36Renew all gaskets.
37Tighten all manifold securing nuts and
bolts progressively to the specified torque.
38Make sure that all hoses, pipes and wires
are securely reconnected in their original
positions.
39On completion, refill the cooling system.
Check the adjustment of the throttle cable
and if necessary adjust the idle speed and
mixture (as applicable).1.6 and 1.8 litre (R6A type) CVH
models
40Disconnect the battery negative lead.
41Remove the air cleaner assembly.
42Depressurise the fuel system and
disconnect the fuel inlet pipe from the CFI unit.
43Disconnect the fuel return pipe from the
CFI unit. Be prepared for fuel spillage.
44Disconnect the throttle cable from the
linkage on the CFI unit.
45Partially drain the cooling system.
46Disconnect the coolant hoses from the
thermostat housing and, whereapplicable,
the CFI unit.
47Disconnect the vacuum and breather
hoses from the inlet manifold and the CFI unit,
noting their locations.
48Disconnect the wiring from the following
components, according to engine type.
Air charge temperature sensor.
Throttle position sensor.
Fuel pressure regulator/injector.
Throttle valve control motor.
Engine coolant temperature sensor.
Cooling fan switch.
Temperature gauge sender.
49Unbolt the dipstick tube from the inlet
manifold, and withdraw the dipstick and
dipstick tube from the cylinder block.
50Make a final check to ensure that all
relevant wires, hoses and pipes have been
disconnected to facilitate removal of the
manifold.
51Unscrew the seven nuts, or six securing
nuts and the single bolt, securing the inlet
manifold to the cylinder head, then lift the
manifold from the cylinder head. Recover the
gasket.
52If desired, the CFI unit can be removed
from the inlet manifold.
53If necessary, the thermostat and housing
can be removed from the manifold.
54Refitting is a reversal of removal, noting
the following points.
55Ensure that all mating faces are clean, and
renew all gaskets.
56Tighten the manifold nuts (and bolt, where
applicable) progressively to the specified
torque.
57Make sure that all wires, hoses and pipes
are reconnected as noted before removal.
58Top-up the cooling system.
59On completion, turn the ignition on and off
five times to pressurise the system, and check
for fuel leaks.
Fuel and exhaust systems - fuel injection 4B•13
4B
30.25b . . . and the throttle linkage30.32 Removing a spark plug spacer from
the cylinder head recess
30.25a Disconnect the throttle cable from
the securing bracket . . .
30.13 Where necessary use two nuts
locked together (arrowed) to remove the
front inlet manifold stud

4Note the locations of the two solenoid
pipes, and the orientation of the solenoid, to
assist with refitting.
5Disconnect the two pipes from the
solenoid, and withdraw the solenoid from its
location.
6Refitting is a reversal of removal. Ensure
that the solenoid pipes are correctly
reconnected, and that the solenoid is
correctly orientated, as noted before removal.
1.6 and 1.8 litre (R6A type) CVH
models
7On 1.6 litre engines, the purge solenoid is
located to the rear of the carbon canister, on
the right-hand side of the engine
compartment. On 1.8 litre engines, the
location varies according to model and
equipment, but can be traced by following the
solenoid pipes back from the carbon canister
(see illustration).
8Proceed as detailed in paragraphs 2 to 6
inclusive.
Note: Do not touch the tip of the HEGO
sensor as this will drastically shorten its
service life.
Note: A new sealing ring should be used on
refitting.
Removal
1Ensure that the engine and the exhaust
system are cold.
2Disconnect the battery negative lead.
3Apply the handbrake, then jack up the front
of the vehicle, and support it securely on axle
stands (see “Jacking and Vehicle Support”).
4Disconnect the sensor wiring plug halves
by releasing the locktabs and pulling on the
plug halves, not the wiring.
5Where fitted, slide the heat shield from the
sensor (see illustration).
6Unscrew the sensor from the exhaust
downpipe, and recover the sealing ring. Do
not touch the tip of the sensor if it is to be
refitted.
Refitting
7Commence refitting by ensuring that the
sensor threads and the corresponding
threads in the downpipe are clean.
8Refit the sensor using a new sealing ring,
and tighten it to the specified torque.
9Further refitting is a reversal of removal, but
on completion start the engine, and check for
leaks around the sensor sealing ring.
2.0 litre SOHC models
1Refer to Chapter 4 Part A, Section 26, but
note the following points.
2Ignore the references to removal and
refitting of the air cleaner and hot air pick-up
pipe, and note that a heat shield is fitted in
place of the hot air shroud.
3Note the location of the inlet manifold
bracing strut which is secured to one of the
manifold studs by an extra nut.
2.0 litre DOHC models
Note: A new manifold gasket must be used on
refitting.
4Disconnect the battery negative lead.
5Disconnect the wiring plug from the idle
speed control valve at the front of the plenum
chamber.
6Loosen the clamp, and detach the air inlet
hose from the air inlet tubing.
7Unscrew the securing nut, and release the
air inlet tube from the bracket on the engine
compartment front panel.
8Release the air cleaner lid securing clips,
then lift away the air inlet tube, plenum
chamber and air cleaner lid as an assembly
disconnecting the breather hose from the air
inlet tube.
9On models with a catalytic converter,
disconnect the exhaust gas oxygen sensor
wiring plug.
10Unscrew the securing nuts, and
disconnect the exhaust downpipe from the
manifold. Recover the gasket. Support the
exhaust downpipe from underneath the
vehicle (eg with an axle stand) to avoid placing
unnecessary strain on the exhaust system.
11Unscrew the six securing nuts, and lift the
manifold from the cylinder head. Recover the
gasket.
12Refitting is a reversal of removal, bearing
in mind the following points.
13Ensure that all mating faces are clean, and
use a new gasket.
14Tighten the manifold securing nuts and
the downpipe securing nuts progressively to
the specified torque (where given).
1.6 and 1.8 litre (R6A type) CVH
models
Note. A new manifold gasket and downpipe
gaskets must be used on refitting.
15Disconnect the battery negative lead.16Remove the air cleaner and, where fitted,
pull the hot-air pick-up pipe from the exhaust
manifold hot-air shroud.
17On 1.6 litre engines, remove the pulse-air
delivery tubing.
18Remove the securing bolts, and withdraw
the hot-air shroud from the manifold.
19Disconnect the exhaust gas oxygen
sensor wiring plug. Unscrew the securing
nuts, and disconnect the exhaust downpipe
from the manifold. Recover the gasket.
Support the exhaust downpipe from
underneath the vehicle (eg with an axle stand)
to avoid placing unnecessary strain on the
exhaust system.
20Unscrew the securing nuts, and lift the
manifold from the cylinder head. Recover the
gasket.
21Refitting is a reversal of removal, bearing
in mind the following points.
22Ensure that all mating faces are clean, and
renew all gaskets.
23Tighten the manifold securing nuts
progressively to the specified torque, and
similarly tighten the exhaust downpipe
securing nuts.
1Refer to Chapter 4 Part A, Section 27.
2On all models except 2.0 litre SOHC,
flanged joints incorporating gaskets may be
used to join exhaust sections on certain
models. Where applicable, renew the gaskets
on refitting.
3On models fitted with a catalytic converter,
disconnect the battery negative lead and
disconnect the exhaust gas oxygen (HEGO)
sensor wiring plug before removing the
downpipe.
37Exhaust system - inspection,
removal and refitting
36Exhaust manifold - removal
and refitting
35Exhaust gas oxygen (HEGO)
sensor (2.0 litre DOHC/1.6 &
1.8 litre (R6A type) CVH) -
removal and refitting
Fuel and exhaust systems - fuel injection 4B•15
4B
35.5 Sliding the heat shield from the
exhaust gas oxygen sensor34.7 Carbon canister-purge solenoid
location (arrowed) - 1.6/1.8 litre (R6A) CVH