ECU LAND ROVER DEFENDER 1996 Owner's Guide

19FUEL SYSTEM
2
DESCRIPTION AND OPERATION A mechanical lift pump, with a hand priming facility, is
driven by the camshaft, and is mounted on the RH
side of the engine.
A fuel filter, with a replaceable element and
incorporating a water separator, is mounted on the
front RH side of the engine compartment.
A fuel sedimentor may be fitted when the vehicle is
operating in more arduous conditions, and is used to
minimise water deposits in the fuel system before
reaching the fuel pump and filter.
Fuel injection is carried out by a Bosch direct injection
pump, incorporating a cold start advance unit and a
high idle setting. The pump is mounted on the RH side
of the engine and is driven directly by gears in the
front cover from the crankshaft. The pump meters and
distributes fuel to 4 pintle type injectors located in
pre-combustion chambers in the cylinder head. Four
heater plugs, located in the cylinder head directly
below each injector, are fitted to improve cold starting.
An optional hand throttle, for use with a centre power
take off, is located on the fascia to the LH side of the
fuse box, and is linked independently to the fuel
injection pump throttle lever.
Air intake
The air cleaner is mounted on the RH side of the
engine and is connected by hoses to the cold air
intake duct and turbocharger inlet. Fitted between the
air cleaner and turbocharger is the crankcase breather
hose which connects to a breather filter on the rocker
cover.
A single stage turbocharger, fitted between the
exhaust manifold and exhaust down pipe, is
connected by hoses to the air cleaner and an
intercooler which is mounted on the LH side of the
radiator. The intercooler is connected by a hose to the
inlet manifold. When an EGR valve is fitted to the
turbocharger, additional pipes/hoses are used to
connect the components.Exhaust gas recirculation (EGR), when fitted.
Exhaust gas recirculation is controlled by an ECU
mounted under the front centre seat or cubby box and
receives the following inputs:
·Engine temperature from coolant temperature
sender unit on LH side of cylinder head.
·Throttle position from potentiometer on injection
pump.
·Engine speed from speedometer.
When all correct signals are received, the EGR
solenoid allows vacuum to open EGR valve and
recirculate a portion of the exhaust gas. See J6196 for
the EGR system component location and 'Operation'
for full system function.

19FUEL SYSTEM
10
DESCRIPTION AND OPERATION Under varying engine speed and load condition the
control unit sends a signal to open the vacuum
modulator which allows a vacuum to be applied above
the EGR diaphragm. The vacuum supply is taken from
a 'T' connector in the brake servo hose. This process
is controlled by an engine speed/load map stored in
the EGR control unit memory.
Engine speed is measured by monitoring the
waveform present on one phase of the generator.
Throttle position is measured via a sensor mounted on
the fuel injection pump throttle lever. Closed loop
control is achieved by allowing the control unit (ECU)
to continually monitor EGR valve lift via the sensor
mounted on the valve; this valve lift is compared with
the actual valve lift required on the control unit map
and adjusted, if necessary.
With coolant temperature between 20°C and 100°C,
the engine having just returned to idle, EGR will shut
off after 25-30 seconds idling.

FUEL SYSTEM
1
ADJUSTMENT THROTTLE CABLE
Adjust
1.Slacken throttle cable adjustment ferrule.
2.Hold throttle lever in fully closed position.
3.Adjust outer cable, by rotating ferrule, to give
1,57 mm (1/16 in) of deflection in the inner cable.
4.Check that throttle opens fully when the throttle
is depressed.EGR THROTTLE POSITION SENSOR
Check
1.Run engine until normal operating temperature is
reached.
2.Switch off engine and disconnect throttle position
sensor multi-plug.
3.Connect an Ohmmeter across pins 1 and 3 of
multi-plug. Ohmmeter should read between 1K
and 1.05K ohms.
4.Connect Ohmmeter across pins 1 and 2 of
multi-plug. Ohmmeter should read between 850
and 900 ohms.
5.If readings are correct, reconnect multi-plug.
6.If readings are not obtained slacken 2 torx
screws securing sensor.
7.Rotate sensor to obtain correct Ohmmeter
reading, then tighten torx screws.
8.Re-check readings and fit multiplug.
9.If, after adjustment, Ohmmeter readings cannot
be achieved, fit new sensor.
See Repair, EGR
throttle position sensor

19FUEL SYSTEM
2
REPAIR
13.Remove banjo bolts securing spill return, main
fuel and boost signal pipes, refit banjo bolts after
disconnecting pipes.
14.Remove 2 bolts securing rear of pump to
mounting bracket.
15.Remove 3 pump securing nuts at flange and
withdraw pump and gasket.
16.Fit suitable caps to pipe connections to prevent
ingress of dirt.
Refit
17.Clean mating faces of pump and front cover and
fit new gasket into position over pump mounting
studs.
18.Remove pump blanking plugs.
19.Slacken the 3 bolts, securing injection pump
mounting bracket to cylinder block, sufficiently
enough to allow bracket to move.
20.Fit pump to cover and secure with 3 nuts.
Tighten to
25 Nm (18 lbf/ft).
21.Loosely attach pump to mounting bracket with
nuts and bolts, then tighten bolts securing
bracket to cylinder block and bolts securing
pump to bracket, finger tight only.
22.To ensure correct fitting and alignment of
injection pump, first tighten the 2 bolts securing
pump to mounting bracket to
25 Nm (18 lbf/ft).
Then tighten the 3 bolts securing mounting
bracket to cylinder block, also to
25 Nm (18
lbf/ft).
23.Connect spill return and main fuel pipes and
secure with banjo bolts. Tighten to
25 Nm (18
lbf/ft).
24.Connect boost signal pipe and secure with banjo
bolt. Tighten to
10 Nm (7 lbf/ft).
25.Connect fuel cut-off solenoid lead and throttle
position sensor multi-plug, if fitted.
26.Connect throttle cable and where applicable,
hand throttle cable.
27.Remove pump gear retaining toolLRT-12-045.
28.Carefully turn the pump hub nut in a clockwise
direction, sufficiently enough to enable timing
tool pin to be inserted into injection pump.
29.Fit gear retaining plate and secure with 3 bolts.
Tighten to
25 Nm (18 lbf/ft).
30.Remove timing pin.
31.Ensure flywheel timing pin is disengaged from
slot in flywheel.
32.Turn crankshaft two complete revolutions, check
timing pin fromRT-12-045can be fully and
easily inserted into the pump. At the same time
check flywheel timing pinLRT-12-044can also
be inserted in the flywheel slot.
33.If, with the flywheel timing pin located, the timing
pin cannot be inserted cleanly into the injection
pump, carry out the following:
a.Ensure flywheel timing pin is disengaged from
slot in flywheel.
b.Slacken the 3 pump gear retaining bolts.
c.Turn the pump hub nut in a clockwise
direction, sufficiently to enable timing tool pin to
be easily inserted into the injection pump.
d.Keeping the tension on the hub nut, check
that flywheel timing pin locates with slot in
flywheel.
e.Tighten the 3 pump gear retaining bolts to
25
Nm (18 lbf/ft).
f.Remove timing pins from pump and flywheel
housing.
34.Using a suitable anti-seize compound, fit the
blanking plug to flywheel housing. Tighten to
12
Nm (9 lbf/ft).
35.Fit access plate with gasket to front cover plate.
Tighten bolts to
25 Nm (18 lbf/ft).
36.Refit injector pipes.
37.Reconnect battery.

FUEL SYSTEM
3
REPAIR FUEL INJECTORS
Service repair no - 19.60.10
Remove
NOTE: When a fuel injector is considered
to be the cause of irregular running and
loss of power it will be necessary to fit a
donor set of injectors to determine which injector
is at fault. DO NOT attempt to dismantle or carry
out spray tests on the fuel injectors. This work
can only carried out by authorised Bosch dealers.
1.Remove oil filler cap and release sound
insulation cover from top of engine.
2.Disconnect high pressure fuel supply pipes from
injectors and injection pump. Remove in pairs.
3.Disconnect spill return hose(s) from injectors.
4.Plug pipes and injector connections to prevent
the ingress of dirt and foriegn matter.5.Remove retaining nut and release each injector
clamp plate from cylinder head.
6.Remove injector and discard copper washer.
Refit
7.Ensure injectors and seating in cylinder head are
clean.
8.Lightly grease a new copper sealing washer and
position on each injector.
9.Fit injectors in cylinder head with spill return
outlets facing outward.
10.Secure injector with clamp plate and nut. Tighten
nut to
25 Nm (18 lbf/ft).
NOTE: The clamp plates are slightly
curved and should be fitted with the
convex side uppermost.
11.Fit the spill return pipe with a single copper
washer under the head of the banjo bolt and 2
copper washers fitted between the injector and
the banjo. Tighten banjo bolt to
10 Nm (7 lbf/ft).
12.Fit high pressure pipes to injectors and injection
pump. Tighten union nuts to
28 Nm (21 lbf/ft).
13.Fit sound insulation cover and oil filler cap.

19FUEL SYSTEM
4
REPAIR FUEL LIFT PUMP
Service repair no - 19.45.09
Remove
NOTE: Blank off pipe ends and
connections to prevent ingress of dirt.
1.Disconnect battery.
2.Remove high pressure fuel pipes, injection pump
to injectors.
3.Disconnect fuel inlet and outlet pipes from lift
pump.
4.Remove 2 bolts and withdraw lift pump and
gasket from cylinder block.
Refit
5.Clean mating faces of pump and cylinder block.
6.Fit lift pump to cylinder block with a new gasket,
ensure correct location of operating lever with
camshaft.
7.Secure with bolts. Tighten to
25 Nm (18 lbf/ft).
8.Connect inlet and outlet pipes using new nuts
and olives.
9.Refit injector pipes. Tighten union nuts to
28 Nm
(21 lbf/ft).
FUEL SEDIMENTOR
Service repair no - 19.25.01
Remove
1.Disconnect battery.
2.Disconnect inlet and outlet fuel pipes from
sedimentor.
3.Slacken drain tap and allow sedimentor to
completely drain.
4.Remove 2 bolts, washers and nuts and detach
sedimentor from chassis mounting bracket.
Refit
5.Secure sedimentor to chassis mounting with
fixing bolts.
6.Reconnect inlet and outlet fuel pipes to
sedimentor.
7.Slacken drain plug until diesel free from air
flows, then retighten plug.
8.Prime vehicle fuel system.
See Adjustment,
Priming the fuel system
9.Reconnect battery.

FUEL SYSTEM
5
REPAIR FUEL FILTER ASSEMBLY
Service repair no - 19.25.02
Remove
1.Disconnect battery.
2.Place a suitable container under filter element
and slacken filter bleed screw.
3.Slacken drain tap and allow fuel to drain from
filter element.
4.Slacken fuel inlet and outlet banjo connections.
5.Remove 2 bolts and nuts securing filter head to
inner wing.
6.Remove fuel inlet and outlet banjo bolts and
detach fuel pipes.
7.Remove filter assembly from vehicle. Unscrew
filter element, if necessary.
8.Plug fuel pipe ends to prevent ingress of dirt.Refit
9.Position filter assembly and fit fuel inlet and
outlet pipes using new copper sealing washers
both sides of the banjo connections.
10.Secure filter head to inner wing.
11.Fully tighten banjo connections.
12.Prime fuel system to remove any air trapped in
filter
See Adjustment, Priming the fuel
system
13.Reconnect battery.
FUEL FILTER ELEMENT
Service repair no - 19.25.07
For remove and refit procedure.
See Fuel filter
element

19FUEL SYSTEM
6
REPAIR SIDE MOUNTED FUEL TANK
Service repair no - 19.55.05
NOTE: This fuel tank is standard on 90
models and an option on 110/130 2 door
vehicles fitted with twin tanks.
Remove
WARNING: Before any attempt is made to
start the removal procedure it is vital that
the FUEL HANDLING PRECAUTIONS are
carefully studied and implemented in the interests
of safety.
See INTRODUCTION, Information, Fuel
Handling Precautions
1.Disconnect battery.
2.Remove fuel filler cap.3.Remove fuel tank drain plug, allow fuel to drain
into a clean container and refit plug.
4.Remove RH seat cushion.
5.Release retaining catch and remove seat base
cover to gain access to fuel tank.
6.Disconnect electrical plug from fuel gauge unit.
7.Disconnect fuel supply pipe from tank.
8.Disconnect spill return pipe from fuel tank.
9.Disconnect breather pipe from fuel filler tube.
10.Slacken hose clip and remove filler hose from
filler tube.
11.From rear of tank, remove 2 nuts and washers
securing tank mounting to captive-headed bolts.
12.Support rear of fuel tank and remove captive
bolts.

FUEL SYSTEM
7
REPAIR REV: 05/99
13.Remove single bolt fixing assembly securing
front of tank to chassis mounted bracket.
14.Remove 3 bolts securing tank mounting bracket
to chassis and release bracket.
15.Lower front of tank while turning anti-clockwise
and remove from vehicle.
16.If required, remove tank gauge unit.
See
INSTRUMENTS, Repair, Fuel gauge tank unit
- side fuel tank
orSee INSTRUMENTS,
Repair, Fuel gauge tank unit - rear fuel tank,
110/130
Refit
17.Fit filler hose and clip to tank but do not fully
tighten. Position clip screw so that it is
accessible when tank is fitted.
18.Fit breather hose and secure with clip.
19.Position fuel tank in vehicle and loosely secure
front mounting bracket to tank with special bolt
and rubber bushes.
20.Secure mounting bracket to chassis with 3 bolts
and fully tighten to
20 Nm (15 lbf/ft).
21.Secure rear of tank to chassis mounting and
tighten captive bolt plate fixings to
20 Nm (15
lbf/ft).
22.Fully tighten front fixing bolt assembly to20 Nm
(15 lbf/ft).
23.Fit spill return and fuel supply pipes and secure
union connections.
24.Fit fuel level unit electrical plug.
25.Fit hose to filler tube and tighten upper and lower
clips.
26.Check that drain plug is secure and fill fuel tank.
27.Reconnect battery.
28.Prime fuel system
See Adjustment, Priming
the fuel system
and start engine.
29.Check system for leaks and operation of fuel
gauge.
30.Fit seat base cover and seat cushion.SIDE MOUNTED FUEL TANK - 5 DOOR VEHICLES
Service repair no - 19.55.01
NOTE: This fuel tank is used on 110/130 5
door vehicles fitted with a twin tank
option.
WARNING: Before any attempt is made to
start the removal procedure it is vital that
the FUEL HANDLING PRECAUTIONS,
See
INTRODUCTION, Information, Fuel handling
precautions
are carefully studied and
implemented in the interests of safety.
Remove
1.Disconnect battery.
2.Remove tank drain plug, allow fuel to drain into a
clean container, and refit plug.
3.Remove RH seat cushion.
4.Remove retaining catch and remove seat base
cover to gain access to fuel tank.
5.Disconnect electrical plug from fuel gauge unit.
6.Disconnect fuel supply pipe from tank.
7.Disconnect spill return pipe from tank.
8.Remove 3 bolts securing tank to front mounting
bracket.
9.Support front of tank and remove single fixing
assembly securing tank to rear mounting
bracket.
10.Remove tank from vehicle.
11.If required, remove fuel gauge unit.
See
INSTRUMENTS, Repair, Fuel gauge tank unit
- side fuel tank
orSee INSTRUMENTS,
Repair, Fuel gauge tank unit - rear fuel tank,
110/130
Refit
12.Position fuel tank in vehicle and loosely secure
to rear mounting bracket with special bolt and
rubber bushes.
13.Secure tank to front mounting bracket and
tighten fixings to
20 Nm (15 lbf/ft).
14.Fully tighten rear fixing bolt assembly to20 Nm
(15 lbf/ft).
15.Fit spill return and fuel supply pipes to fuel tank
and securely tighten union connectios.
16.Fit electrical plug to fuel gauge unit.
17.Check that drain plug is secure and fill fuel tank.
18.Reconnect battery.
19.Prime fuel system.
See Adjustment, Priming
the fuel system
and start engine.
20.Check system for leaks and operation of fuel
gauge.
21.Fit seat base cover and seat cushion.

FUEL SYSTEM
9
REPAIR REV: 05/99
11.Remove 2 nuts that secure front fixing assembly
of the tank to chassis mounting bracket.
12.Remove tank rear mounting nuts.
13.With care, lower tank sufficiently to enable nut
and olive of spill return to be disconnected from
elbow in centre of tank.
14.Continue to lower tank until it can be removed
from vehicle.
NOTE: On later vehicles a separate stone
guard is fitted and is attached to the tank
with the existing front and rear fixings.
15.If required, remove tank gauge unit.
See
INSTRUMENTS, Repair, Fuel gauge tank unit
- side fuel tank
orSee INSTRUMENTS,
Repair, Fuel gauge tank unit - rear fuel tank,
110/130
Refit
16.If applicable, locate stone guard under tank.
17.Raise rear tank into position and connect spill
return pipe to the elbow with the nut and olive.
18.Continue to raise tank so that front and rear
mounting bolts locate in respective tank flange
holes.
19.Fit and tighten fixings to
20 Nm (15 lbf/ft).
20.Connect fuel suppnly pipe to the tank unit.
21.Fit fuel filler hose and breather pipe to filler tube
and secure with retaining clips.
22.Fit LH lashing eye to chassis.23.Fit anti-roll bar chassis mountings.
See REAR
SUSPENSION, Repair, Anti-roll bar
24.Check that drain plug is secure and fill fuel tank.
25.Reconnect battery.
26.Prime fuel system.
See Adjustment, Priming
the fuel system
and start engine.
27.Check system for leaks and operation of fuel
gauge.