1999 LAND ROVER DEFENDER cooling

17EMISSION CONTROL
2
REPAIR VALVE - EGR - EU3 MODELS
Service repair no - 17.45.01
Remove
1.Release turnbuckles and remove battery cover.
2.Disconnect battery earth lead.
3.Remove 3 bolts and remove engine acoustic
cover.
4.Remove cooling fan coupling.See COOLING
SYSTEM, Repair.
5.Disconnect vacuum hose(s) from EGR valve.
6.Loosen screw and disconnect air intake hose
from EGR valve.
7.Remove screw and remove clamp securing EGR
pipe to EGR valve.
8.Remove 4 bolts securing EGR valve, remove
valve and discard gasket.
9.Discard EGR pipe gasket.Refit
10.Clean EGR valve and mating faces.
11.Fit new gasket to EGR pipe.
12.Using new gasket, position EGR valve to inlet
manifold fit bolts and tighten to10 Nm (7 lbf.ft).
13.Fit EGR pipe clamp and tighten screw to6Nm
(4.4 lbf.ft).
14.Connect air intake hose to EGR valve and
tighten clip.
15.Connect vacuum hoses to EGR valve.
16.Fit cooling fan coupling.See COOLING
SYSTEM, Repair.
17.Fit engine acoustic cover and tighten bolts to10
Nm (7 lbf.ft).
18.Connect battery earth lead.
19.Fit battery cover and secure the fixings.
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ENGINE MANAGEMENT SYSTEM
3
DESCRIPTION AND OPERATION 1.Mass Air Flow (MAF) sensor.
2.Engine Coolant Temperature (ECT) sensor.
3.Glow plugs.
4.Manifold Absolute Pressure (MAP) / Inlet Air Temperature (IAT) sensor.
5.Fuel pump relay.
6.Engine Control Module (ECM).
7.Air Conditioning (A/C) and cooling fan relay.
8.Fuel Temperature (FT) sensor.
9.Crankshaft Speed and Position (CKP) sensor.
10.Electronic Unit Injectors (EUI).
11.Ambient Air Pressure (AAP) sensor.
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ENGINE MANAGEMENT SYSTEM
5
DESCRIPTION AND OPERATION DESCRIPTION
General
An engine control module (ECM) controls the five cylinder direct injection diesel engine, and works on the drive by
wire principal. This means there is no throttle cable, the ECM controls the drivers needs via a signal from the
Throttle Position (TP) sensor on the throttle pedal.
The ECM is a full authoritative diesel specific microprocessor that also incorporates features for air conditioning. In
addition, the ECM supplies output control for the Exhaust Gas Recirculation (EGR) and turbocharger boost
pressure. The ECM has a self diagnostic function, which is able to provide backup strategies for most sensor
failures.
The ECM processes information from the following input sources:
Mass Air Flow (MAF) sensor.
Ambient Air Pressure (AAP) sensor.
Manifold Absolute Pressure (MAP) / Inlet Air Temperature (IAT) sensor.
Engine Coolant Temperature (ECT) sensor.
Crankshaft Speed and Position (CKP) sensor.
Throttle Position (TP) sensor.
Fuel Temperature (FT) sensor.
Air conditioning request.
Air conditioning fan request.
Brake pedal switch.
Clutch pedal switch.
The input from the sensors constantly updates the ECM with the current operating condition of the engine. Once
the ECM has compared current information with stored information within its memory, it can make any adjustment
it requires to the operation of the engine via the following:
Air conditioning clutch relay.
Air conditioning cooling fan relay.
Electronic vacuum regulator solenoid.
Fuel pump relay.
Glow plug warning lamp.
Glow plugs.
Fuel injectors.
Main relay.
Turbocharger wastegate modulator.
Temperature gauge.
The ECM interfaces with the following:
Serial communication link.
Instrument pack.
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ENGINE MANAGEMENT SYSTEM
11
DESCRIPTION AND OPERATION SENSOR - ENGINE COOLANT TEMPERATURE
(ECT)
The ECT sensor is located in the coolant outlet elbow on top of the engine. It provides the ECM with engine
coolant temperature information. The ECM uses this information for the following functions:
Fuelling calculations.
Temperature gauge.
To limit engine operation if coolant temperature is to high.
Cooling fan operation.
Glow plug operating time.
The ECT works as an NTC sensor. As temperature rises, the resistance in the sensor decreases, as temperature
decreases, the resistance in the sensor increases. The ECM compares the voltage signal to stored values and
compensates fuel delivery to ensure optimum driveability at all times.
Inputs / Outputs
The ECT sensor (C0169-2) is provided a feed by the ECM (C0158-7) on a pink/green wire. The sensor is provided
an earth path (C0169-1) via the ECM (C0158-18) on a pink/black wire.
The ECT can fail or supply an incorrect signal if one or more of the following occurs:
Sensor open circuit.
Short circuit to vehicle supply.
Short circuit to vehicle earth.
Incorrect mechanical fitting.
Signal fixed above 40°C (104°F) not detected.
Signal fixed below 40°C (104°F) not detected.
In the event of an ECT sensor failure, any of the following symptoms may be observed:
Difficult cold start.
Difficult hot start.
Driveability concerns.
Instrument pack warning lamp illuminated.
Temperature gauge reads excessively hot.
Temperature gauge reads excessively cold.
In the event of a component failure the ECM calculates coolant temperature from the fuel temperature signal. If
this occurs, the limit of engine operation if coolant temperature becomes too high becomes inoperative.
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ENGINE MANAGEMENT SYSTEM
1
REPAIR ENGINE CONTROL MODULE (ECM)
Service repair no - 18.30.03
Remove
1.Release fixings and remove battery cover.
2.Disconnect battery negative lead.
3.Remove RH seat cushion, release clip and
remove ECM access panel.
4.Remove 3 bolts, release ECM and disconnect 2
multiplugs. Remove ECM.
Refit
5.Position new ECM and connect multiplugs.
6.Fit ECM and tighten bolts.
7.Fit access panel and RH seat cushion.
8.Reconnect battery negative lead.
9.Fit battery cover and secure with fixings.SENSOR - ENGINE COOLANT TEMPERATURE
(ECT)
Service repair no - 18.30.10
Remove
1.Disconnect battery negative lead.
2.Remove spring clip and disconnect ECT sensor
multiplug.
3.Position cloth around ECT sensor to absorb
coolant spillage.
4.Remove ECT sensor.
5.Remove sealing washer and discard.
Refit
6.Clean sealing washer, sensor threads and
sensor location.
7.Coat sensor threads with Loctite 577 and fit new
sealing washer.
8.Fit ECT sensor and tighten to20 Nm (14 lbf.ft).
9.Fit spring clip to multiplug and connect multiplug
to ECT sensor.
10.Top up cooling system.
11.Run engine to normal operating temperature.
Check for leaks around ECT sensor.
12.Reconnect battery negative lead.
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19FUEL SYSTEM
4
REPAIR ELEMENT - FUEL FILTER
Service repair no - 19.25.07
Remove
1.Release fixings and remove battery cover.
2.Disconnect battery negative lead.
3.Raise rear of vehicle.
WARNING: Support on safety stands.
4.Release fixing and remove fuel filter cover.
5.Clean area around fuel filter.
6.Disconnect multiplug from filter element.
7.Remove fuel filter element.
Refit
8.Clean fuel filter and mating face.
9.Fit new fuel filter element and connect multiplug.
10.Position fuel filter cover and secure with fixing.
11.Remove stand(s) and lower vehicle.
12.Reconnect battery negative lead.
13.Fit and secure battery cover.COOLER - FUEL
Service repair no - 19.25.30
Remove
1.Remove 3 bolts and remove engine acoustic
cover.
2.Remove battery cover.
3.Disconnect battery negative lead.
4.Drain cooling system.See COOLING
SYSTEM, Adjustment.
5.Release 3 clips and disconnect 3 coolant hoses
from fuel cooler.
6.Release 2 fuel hoses from fuel cooler.
CAUTION: Plug the connections.
7.Release vacuum pipe clip from fuel cooler.
8.Remove 4 bolts securing fuel cooler to inlet
manifold and remove cooler.
Refit
9.Clean fuel hose connections.
10.Position fuel cooler to inlet manifold. Apply
Loctite 242 to bolts and tighten to18 Nm (13
lbf.ft).
11.Connect fuel hoses.
12.Connect coolant hoses, secure with clips.
13.Secure vacuum hose to fuel cooler.
14.Refill cooling system.See COOLING SYSTEM,
Adjustment.
15.Fit engine acoustic cover and secure with bolts.
16.Reconnect battery negative lead.
17.Fit battery cover.
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FUEL SYSTEM
7
REPAIR Refit
7.Clean air flow meter faces.
8.Fit new’O’ring to air filter.
9.Clean AAP sensor.
10.Using new’O’ring, fit AAP sensor and tighten
screws.
11.Position air filter assembly and secure in
grommets.
12.Position air flow meter and secure clips.
13.Position intake hose to air filter and tighten clip
screw.INJECTOR - SET
Service repair no - 19.60.12
Remove
1.Remove cooling fan.See COOLING SYSTEM,
Repair.
2.Remove rocker shaft.See ENGINE , Repair.
3.Position container to catch fuel spillage.
4.Disconnect quick release fuel hose connectors
from fuel connector block on cylinder head and
fuel cooler to drain fuel from cylinder head.
5.Disconnect 5 multiplugs from injectors.
6.Remove Torx bolt securing injector unit to
cylinder head.
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19FUEL SYSTEM
8
REPAIR
7.AssembleLRT-12-154/1to injector unit, screw in
slide hammer and remove injector.
8.UsingLRT-12-154/4,remove and discard
sealing washer.9.Remove and discard’O’ring seal.
10.Rotate engine to align camshaft lobes for access
of injector removal tool.
11.Carry out above procedure to remove the
remaining 4 injectors.
12.Rotate engine manually until each cylinder being
worked on is at TDC, and remove excess fuel
from piston bowl using a syringe.
Refit
13.Clean injector unit and mating faces in cylinder
head.
14.PositionLRT-12-154/2to injector units and fit
new’O’rings.
15.Fit new sealing washers to injector nozzles using
LRT-12-154/3.
16.Fit retainers to injectors, carefully fit injectors
ensuring retainer is located on its dowel and
tighten bolt to32 Nm (24 lbf.ft)
17.Connect multiplug to injector.
18.Repeat above operation for remaining injectors.
19.Connect fuel hoses.
20.New injectors must be programmed using
TestBook.
21.Fit rocker shaft.See ENGINE , Repair.
22.Fit cooling fan.See COOLING SYSTEM,
Repair.
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