1999 LAND ROVER DEFENDER fuel consumption

GENERAL SPECIFICATION DATA
3
INFORMATION FUEL SYSTEM - Td5
Type Direct injection from pressure regulated supply with.................................................................................
cooled return flow
Pressure regulator setting 4 bar (58 lbf.in
2) ................................................
Pump Electric two stage submersible................................................................................
Pump output
Low pressure 30 l/h (6.6 gal/h) at 0.5 bar (7.25 lbf.in
2) ..........................................................
High pressure 180 l/h (39.6 gal/h) at 4 bar (58 lbf.in2) ..........................................................
Max consumption 30 l/h (6.6 gal/h).............................................................
Injectors Electronic unit injectors...........................................................................
Injector normal operating pressure 1500 bar (21750 lbf.in
2) ..................................
Filter In-line canister filter/water separator with water.................................................................................
detection
COOLING SYSTEM - Td5
Type Pressurised spill return partial flow, thermostatically.................................................................................
controlled
Cooling fans 11 blade axial flow on viscous coupling and 11 blade.....................................................................
axial flow electric
Electric cooling fan switching points
On Vehicle speeds of 50 mph (80 km/h) and below while...........................................................................
ambient temperature is 28°C (82°F) or above
Off Vehicle speeds of 62.5 mph (100 km/h) and above or...........................................................................
ambient temperatures of 25°C (77°F) and below
Coolant pump Centrifugal impeller, belt driven from crankshaft...................................................................
Thermostat Waxstat with pressure relief valve.......................................................................
Thermostat opening temperature
Initial opening 82°C (179°F) ..........................................................
Fully open 96°C (204°F) ...............................................................
Expansion tank cap relief valve operating pressure 1.4 bar (20.3 lbf.in
2) .........
CLUTCH - Td5
Type Diaphragm spring, hydraulically operated with.................................................................................
self-centering pre-loaded release bearing
Drive plate diameter 267 mm.........................................................
Pressure plate diameter 270 mm...................................................
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09LUBRICANTS, FLUIDS AND CAPACITIES
2
INFORMATION Propeller shaft Front
and RearNLGI - 2 Multi-purpose Lithium based GREASE
Lubrication nipples
(hubs, ball joints
etc.)
Seat slides
Door lock striker
Brake and clutch
reservoirsBrake fluids having a minimum boiling point of 260°C (500°F) and complying with
FMVSS 116 DOT4
Engine coolant Use Texaco XLC long life coolant. Use one part anti-freeze to one part water for
protection down to -36°C (-33°F).
IMPORTANT: Coolant solution must not fall below 50% anti-freeze otherwise
damage to engine is liable to occur. Maximun concentration is 60%.
Battery lugs, Petroleum jelly.
Earthing surfacesNOTE: Do not use Silicone Grease
where paint has
been removed
Air Conditioning
System Refrigerant Use only refrigerant R134a
Compressor Oil ND-OIL 8
LUBRICATION PRACTICE
Use a high quality oil of the correct viscosity range and service classification in the engine during maintenance and
when topping up. The use of oil not to the correct specification can lead to high oil and fuel consumption and
ultimately to damaged components.
Oil to the correct specification contains additives which disperse the corrosive acids formed by combustion and
prevent the formation of sludge which can block the oilways. Additional oil additives should not be used. Always
adhere to the recommended servicing intervals.
WARNING: Many liquids and other substances used in motor vehicles are poisonous. They must
not be consumed and must be kept away from open wounds. These substances, among others,
include anti-freeze, windscreen washer additives, lubricants and various adhesives.
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18ENGINE MANAGEMENT SYSTEM
22
DESCRIPTION AND OPERATION SWITCH - BRAKE PEDAL
The brake pedal switch is located at the rear of the brake pedal box, and activates when the brake pedal is
operated. The ECM uses the signal from the brake pedal to activate the brake lamps and to limit fuelling under
braking.
The brake pedal switch can fail in any of the following ways:
Switch open circuit.
Short circuit to vehicle supply.
Short circuit to earth.
SWITCH - CLUTCH PEDAL
The clutch pedal switch is located on the clutch master cylinder and is activated when the clutch pedal is operated.
The ECM uses the signal from the clutch pedal switch to provide surge damping during gear change. Surge
damping stops engine speed rising dramatically (engine flaring) during gear change. Surge damping assists
driveability as follows:
Smoother gear change.
Greater exhaust gas emission control.
Improved fuel consumption.
Input / Output
When the clutch pedal is in the rest position, the clutch switch is closed. This allows a feed to flow from the switch
(C0667-1) to the ECM (C0658-35) on a black/white wire. When the clutch pedal is pressed the switch contacts
open, cutting the feed to the ECM.
The clutch pedal switch can fail in any one of the following ways:
Switch open circuit.
Short circuit to vehicle supply.
Short circuit to vehicle earth.
In the event of a clutch pedal switch failure surge damping will be inactive.
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18ENGINE MANAGEMENT SYSTEM
26
DESCRIPTION AND OPERATION TURBOCHARGER
1.Exhaust gas from manifold
2.Studs to exhaust manifold
3.Turbocharger cast iron housing
4.Wastegate valve linkage
5.Exhaust gas out to front exhaust pipe6.Compressed air intake
7.Fresh air intake
8.Turbocharger aluminium alloy housing
9.Wastegate valve vacuum port
The Td5 engine utilises a Garrett GT20 turbocharger with an electronically controlled wastegate modulator to
improve engine performance. The turbocharger uses the engines exhaust gas to spin a turbine at very high
speed. This causes inlet air on the other side of the turbine to be drawn in through the turbocharger intake for
compression.The inlet air is carried round by the vanes of the compressor and then thrown out under centrifugal
force from the turbochargers outlet duct. This compression of air enables a greater quantity of air to be delivered
to the inlet manifold via an intercooler. Combustion is improved through better volumetric efficiency. The use of a
turbocharger improves fuel consumption and increases engine torque and power. Exhaust noise is also reduced
due to the smoothing out of exhaust pulsations.
The rear cast iron body of the turbocharger housing connects to a port on the exhaust manifold at the LH side of
the cylinder head by three studs and nuts. The interface between the exhaust manifold and the turbocharger
housing is separated by a metal gasket. The exhaust outlet of the turbocharger is located at the bottom of the
turbocharger cast iron housing. It is connected to the exhaust system front downpipe and is attached by three
studs and nuts. The interface between the turbocharger housing and the exhaust front pipe is separated by a
metal gasket.
The front casing of the turbocharger is constructed from aluminium alloy and is connected to the air inlet duct by a
metal band clip. The compressed air outlet is connected to the intercooler by a metal pipe which has rubber hose
extensions at each end attached by metal band clips.
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18ENGINE MANAGEMENT SYSTEM
28
DESCRIPTION AND OPERATION OPERATION
Engine Management
The ECM controls the operation of the engine using stored information within its memory. This guarantees
optimum performance from the engine in terms of torque delivery, fuel consumption and exhaust emissions in all
operating conditions, while still giving optimum driveability.
The ECM will receive information from its sensors under all operating conditions, especially during:
Cold starting.
Hot starting.
Idle.
Wide open throttle.
Acceleration.
Adaptive strategy.
Backup strategy for sensor failures.
The ECM receives information from various sensors to determine the current operating state of the engine. The
ECM then refers this information to stored values in its memory and makes any necessary changes to optimise
air/fuel mixture and fuel injection timing. The ECM controls the air/fuel mixture and fuel injection timing via the
Electronic Unit Injectors (EUI), by the length of time the EUI’s are to inject fuel into the cylinder. This is a rolling
process and is called adaptive strategy. By using this adaptive strategy the ECM is able to control the engine to
give optimum driveability under all operating conditions.
During cold start conditions the ECM uses ECT information to allow more fuel to be injected into the cylinders.
This, combined with the glow plug timing strategy supplied by the ECM, facilitates good cold starting.
During hot start conditions, the ECM uses ECT and FT information to implement the optimum fuelling strategy to
facilitate good hot starting.
During idle and wide open throttle conditions, the ECM uses mapped information within its memory to respond to
input information from the TP sensor to implement the optimum fuelling strategy to facilitate idle and wide open
throttle.
To achieve an adaptive strategy for acceleration, the ECM uses input information from the CKP sensor, the TP
sensor, the ECT sensor, the MAP/IAT sensor, and the FT sensor. This is compared to mapped information within
its memory to implement the optimum fuelling strategy to facilitate acceleration.
Fuel Delivery / Injection Control
The fuel delivery/injection control delivers a precise amount of finely atomised fuel to mix with the air in the
combustion chamber to create a controlled explosion. To precisely control fuel delivery and control fuel injection,
the following input conditions must be met:
CKP information.
Injection timing map information.
FT information.
ECT information.
The ECM monitors the conditions required for optimum combustion of fuel in the cylinder from the various sensors
around the engine and then compares it against stored information. From this calculation, the ECM can adjust the
quantity and timing of the fuel being delivered into the cylinder. The ECM uses CKP information as follows:
To calculate engine speed.
To determine engine crankshaft position.
Engine speed and crankshaft position allows the ECM to determine fuel injection timing.
The ECM also uses ECT and FT information to allow optimum fuel delivery and injection control for all engine
coolant and fuel temperatures.
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26COOLING SYSTEM
10
DESCRIPTION AND OPERATION At low radiator temperatures, the fan operation is not required and the bi-metallic coil keeps the valve closed,
separating the silicone fluid from the drive plate. This allows the fan to’freewheel’reducing the load on the engine,
improving fuel consumption and reducing noise generated by the rotation of the fan.
When the radiator temperature increases, the bi-metallic coil reacts and moves the valve, allowing silicone fluid to
flow into the fluid chamber. The resistance to shear of the silicone fluid creates drag on the drive plate and
provides drive to the body and the fan blades.
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