oil temperature LAND ROVER DISCOVERY 1995 User Guide

12ENGINE
6
DESCRIPTION AND OPERATION CYLINDER HEAD COMPONENTS
1. Engine oil filler cap
2. Filler cap seal
3. Screw - spark plug cover
4. Spark plug cover
5. h.t. lead plate
6. Screw - h.t. lead plate
7. Inlet camshaft cover
8. Exhaust camshaft cover
9. Bolt - exhaust camshaft cover
10. Exhaust camshaft cover gasket/baffle plate
11. Bolt - exhaust camshaft carrier
12. Exhaust camshaft carrier
13. Exhaust camshaft
14. Cylinder head bolt
15. Blanking plate
16. Bolt - blanking plate
17. Locating dowel - camshaft carrier
18. Coolant outlet elbow
19. Gasket
20. Bolt - coolant outlet elbow
21. Stud - exhaust manifold
22. Cylinder head gasket
23. Guide - exhaust valve24. Insert - exhaust valve seat
25. Exhaust valves
26. Inlet valves
27. Insert - inlet valve seat
28. Guide - inlet valve
29. Cylinder head
30. Stud - inlet manifold
31. Valve stem oil seal
32. Valve spring
33. Valve spring cap
34. Collets
35. Tappet
36. Camshaft oil seals
37. Drive pins - camshaft timing gears
38. Inlet camshaft
39. Inlet camshaft carrier
40. Bolt - inlet camshaft carrier
41. Inlet camshaft cover gasket/baffle plate
42. Bolt - inlet camshaft cover
43. Spark plug
44. Coolant temperature sensor
NOTE: Items 15,16 & 36 on current engines
replaced by an oil plug.
See Repair, Inlet -
Exhaust Camshaft Rear Oil Plug

Mpi
9
REPAIR 29.Disconnect oil pressure switch multiplug.
30.Disconnect air conditioning compressor
multiplug.
31.Remove 3 bolts securing engine harness to
manifold and fuel pipe.
32.Disconnect knock sensor multiplug.
33.Remove 2 nuts securing harness to starter motor
solenoid, remove harness.
34.Disconnect crankshaft sensor multiplug.
35.Disconnect fuel injection harness multiplug.
36.Disconnect inlet manifold air temperature sensor
multiplug.
37.Release clip and disconnect fuel hose from
pressure regulator.
CAUTION: Plug the connections.

Mpi
13
REPAIR 19.Connect crankshaft sensor, knock sensor, air
conditioning compressor, fuel injector harness,
inlet manifold air temperature and fuel
temperature sensor multiplugs.
20.Connect fuel hose to pressure regulator and
secure with clip.
21.Fit and tighten fuel pipe to fuel rail union.
22.Connect multiplugs to throttle housing.
23.Connect vacuum hose to manifold.
24.Connect oil pressure switch multiplug.
25.Connect brake servo hose to manifold, secure
with clip.
26.Connect throttle cable to cam.
27.Position engine harness and connect breather
hose to inlet manifold, secure with clip.
28.Connect coolant temperature sensor multiplugs,
secure harness with cable tie.
29.Connect oxygen sensor multiplug, secure
harness with cable tie.
30.Connect alternator harness.
31.Connect heater hose to heater rail and secure
with clip.
32.Connect hose to coolant pump and secure with
clip.
33.Connect inlet hose to power steering pump and
secure with clip.
34.Fit and tighten outlet pipe union to power
steering pump.
35.Connect bypass and top hose, secure with clip.
36.Connect air cleaner to throttle housing hose and
secure with clip.
37.Remove engine lifting bracket.
38.Position spark plug cover and secure with
screws.
39.Fill engine with oil.
40.Fit bonnet [hood].
See CHASSIS AND BODY,
Repair, Bonnet [Hood]
41.Fit radiator.See COOLING SYSTEM, Repair,
Radiator - Mpi
42.Adjust throttle cable.See FUEL SYSTEM,
Adjustment, Throttle Cable Adjustment
ENGINE SUMP GASKET
Service repair no - 12.60.43
Remove
1.Drain engine oil.
2.Refit drain plug, use new sealing washer if
necessary, tighten to the correct torque.
3.Remove 18 bolts securing sump.
NOTE: 25mm long bolt is fitted at rear L.H.
corner of sump.
4.Release sump from cylinder block.
5.Discard gasket.

Mpi
1
SPECIFICATIONS, TORQUE TORQUE VALUES
NOTE: Torque wrenches should be regularly checked for accuracy to ensure that all fixings are
tightened to the correct torque.
Nm
ENGINE
Timing belt upper cover bolts 5......................................................................
Timing belt centre cover bolts 5.....................................................................
Timing belt lower cover bolts 5......................................................................
Crankshaft pulley centre bolt 85.....................................................................
Crankshaft pulley to timing gear bolts 10........................................................
Tensioner pulley bolt 30..................................................................................
Spark plugs 27................................................................................................
Timing belt upper backplate bolts 10..............................................................
Camshaft gear bolts 65...................................................................................
Exhaust camshaft rear oil seal cover plate bolts 10........................................
Inlet camshaft rear oil seal cover plate bolts 10..............................................
Crankshaft rear oil seal housing bolts 10........................................................
Engine sump bolts
Stage 1 3...............................................................................................
Stage 2 10..............................................................................................
Bell housing nuts 40........................................................................................
L.H. and R.H. engine mounting nuts 85..........................................................
Exhaust manifold to downpipe nuts 10...........................................................
Exhaust downpipe to silencer box nuts 30......................................................
Air conditioning compressor to engine block bolts 45.....................................
Cylinder head bolts
Stage 1 45..............................................................................................
Stage 2 80..............................................................................................
Stage 3 - Further 90°
Camshaft cover bolts 10.................................................................................
Knock sensor 15.............................................................................................
Ignition coil bracket bolts 25............................................................................
Coolant temperature sensor 15......................................................................
Crankshaft sensor bolts 7..............................................................................
Fuel temperature sensor 7.............................................................................
Intake air temperature sensor 7.....................................................................
Fuel rail to inlet manifold bolts 10...................................................................
Fuel feed hose stiffening bracket bolts 7.......................................................
Throttle housing mounting nuts 7...................................................................
Fuel pressure regulator steady bracket bolts 7..............................................
Oxygen sensor 55...........................................................................................

19FUEL SYSTEM
8
REPAIR
All glow plugs
5.Remove terminal nut from glow plug, disconnect
wire from glow plug terminal.
6.Remove glow plug.
Refit
7.Clean glow plug and seating.
8.Coat threads of glow plug with suitable anti-seize
compound operational to a temperature of
1000°C.
9.Fit glow plug. Tighten to
23 Nm.
10.Connect wire to glow plug terminal and secure
with nut.
NOTE: Feed wire must be connected to
No. 4 glow plug terminal.
11.
No. 3 glow plug:Lubricate new 'O' ring with
engine oil and fit to Hummel valve. Fit valve and
secure with bolt. Tighten to
15 Nm.
No. 1 glow plug - air conditioning models
12.Position compressor to front cover, fit bolts.
Tighten to
25 Nm.
13.Fit drive belt to compressor pulley and adjust
tension.
See ENGINE, Repair, Drive Belt
Renew
All models
14.Reconnect battery negative lead.EGR VALVE
Service repair no - 19.45.01
Remove
1.Disconnect multiplug from EGR valve.
2.Disconnect vacuum pipe from EGR valve.
3.Remove 2 Allen screws securing EGR valve to
exhaust manifold.
4.Remove 2 bolts securing hose to EGR valve.
5.Remove EGR valve and discard gaskets.
Refit
6.Clean mating faces of EGR valve and exhaust
manifold.
7.Reverse removal procedure. Tighten bolts to
25
Nm.

19FUEL SYSTEM
2
DESCRIPTION AND OPERATION REV: 09/95 ENGINE MANAGEMENT SYSTEM COMPONENT
LOCATION - PRE ADVANCED EVAPS
1. Engine control module
2. Ignition coils
3. Fuel pressure regulator
4. Mass air flow sensor
5. Relay module
- Main relay
- Fuel pump relay
6. Engine coolant temperature sensor
7. Camshaft position sensor
8. Throttle position sensor

SFI
5
DESCRIPTION AND OPERATION REV: 09/95 Engine fuel temperature sensor (EFT Sensor)
This is another resistive sensor. Located on the fuel
rail it measures temperature of the rail rather than the
fuel. The resistance varies with changes in
temperature. The signal is used to increase the
injection pulse time when undergoing hot restarts.
When the fuel is hot, vapourisation occurs in the rail
and bubbles can occur in the injectors. Increasing the
pulse time flushes the bubbles away, and cools the
fuel rail with fuel from the tank. The fault may not be
evident to the driver, there may be a hot restart
problem. The fault is indicated by illumination of the
malfunction indicator light (MIL) on North American
specification vehicles.
Knock sensors
The knock sensor produces an output voltage in
proportion to mechanical vibration caused by the
engine. A sensor is located in each cylinder bank
between 2/4 and 3/5 cylinders. The ECM calculates if
the engine is knocking due to camshaft and
crankshaft sensor signals regarding the position of the
engine in the cycle. The ECM can also work out
exactly which cylinder is knocking and retards the
ignition on that particular cylinder until the knock
disappears. It then advances the ignition to find the
optimum ignition timing for that cylinder. The ECM can
adjust the timing of each cylinder for knock
simultaneously. It is possible that all eight cylinders
could have different advance angles at the same time.
If the camshaft sensor fails, the knock sensor will
continue to work, but as the engine may be running
one revolution out of sychronisation the ECM may
retard the wrong cylinder of the pair e.g. 1 instead of
6. If the knock sensor fails engine knock will not be
detected and corrected. The fault is indicated by
illumination of the malfunction indicator light (MIL) on
North American specification vehicles.Ignition coils
The electronic ignition system uses four double ended
coils. They are mounted on a bracket fitted to the rear
of the engine. The circuit to each coil is completed by
switching within the ECM, allowing each coil to charge
up and fire. Sparks are produced in two cylinders
simultaneously, one on compression stroke, the other
on exhaust stroke. Note that coil 1 feeds cylinders 1
and 6, coil 2 feeds cylinders 5 and 8, coil 3 feeds
cylinders 4 and 7, and coil 4 feeds cylinders 2 and 3.
Due to the ease of combustion in the cylinder on the
compression stroke, more energy is dissipated in that
cylinder. Coil failure will result in a lack of sparks and
misfire in the affected cylinders. The fault is indicated
by illumination of the malfunction indicator light (MIL)
on North American specification vehicles.
Injectors
A multiport fuel injection system (MFI) is used, one
injector per cylinder. Each injector consists of a small
solenoid which is activated by the ECM to allow a
metered amount of fuel to pass into the combustion
chamber. Due to the pressure in the fuel rail and the
shape of the injector orifice, the fuel squirts into the
cylinder in a fine spray to aid combustion. In the
unlikely event of injector failure a misfire will occur as
there will be no fuel to the affected cylinder. The fault
is indicated by illumination of the malfunction indicator
light (MIL) on North American specification vehicles.

19FUEL SYSTEM
6
DESCRIPTION AND OPERATION REV: 09/95 Idle air control (IAC)
Idle speed is controlled by a stepper motor which
consists of two coils. When energised in the correct
sequence the coils move a plunger which opens and
closes the throttle bypass controlling the quantity of
idle air. The stepper motor controls idle speed by
moving the plunger a set distance called a step. Fully
open is zero steps and fully closed 180 steps. Failure
of the stepper motor will result in low or high idle
speed, poor idle, engine stall or non start. The fault is
indicated by illumination of the malfunction indicator
light (MIL) on North American specification vehicles.Heated oxygen sensor (HO2S)
The oxygen sensors consist of a titanium metal
sensor surrounded by a gas permeable ceramic
coating. Oxygen in the exhaust gas diffuses through
the ceramic coating on the sensor, and reacts with the
titanium wire altering the resistance of the wire. From
this resistance change the ECM calculates the
amount of oxygen in the exhaust gas. The injected
fuel quantity is then adjusted to achieve the correct
air/fuel ratio, thus reducing the emissions of carbon
monoxide (CO), hydrocarbons (HC),and oxides of
nitrogen (NO
2). Two HO2 sensors are fitted, one in
each exhaust downpipe just ahead of the catalyst.
Note that if the wiring to these sensors is crossed, the
vehicle will start and idle correctly until the sensors
reach operating temperature. Then the ECM will read
the signals from them and send one bank of cylinders
very rich and the other very weak. The engine will
misfire, have a rough idle and emit black smoke, with
possible catalyst damage.
In the event of sensor failure, the system will default to
'open loop'. Operation and fuelling will be calculated
using signals from the remaining ECM inputs.
The fault is indicated by illumination of the malfunction
indicator light (MIL). ECM diagnostics also uses HO2
sensors to detect catalyst damage, misfire and fuel
system faults.
North American vehicles have two extra HO2 sensors
mounted one after each catalyst. These are used to
determine whether the catalysts are operating
efficently.
CAUTION: Although robust within the
vehicle environment, HO2 sensors are
easily damaged by dropping, excessive
heat and contamination. Care must be exercised
when working on the exhaust system not to
damage the sensor housing or tip.

19FUEL SYSTEM
8
DESCRIPTION AND OPERATION ADD: 09/95 ENGINE MANAGEMENT SYSTEM COMPONENT
LOCATION - ADVANCED EVAPS
1.Engine control module (ECM)
2.Ignition coils
3.Fuel pressure regulator
4.Mass air flow (MAF) sensor
5.Relay module
- Main relay
- Fuel pump relay
6.Engine coolant temperature (ECT) sensor
7.Camshaft position (CMP) sensor
8.Throttle position (TP) sensor

19FUEL SYSTEM
6
REPAIR 15.Disconnect hose, plug return hose and rail.
Remove cloth.
16.Remove 6 nuts securing fuel rail and ignition coil
bracket to inlet manifold.
17.Release ignition coil bracket from inlet manifold
studs. Place aside.
18.Release fuel rail and injectors from inlet
manifold.
Do not carry out further dismantling if component
is removed for access only.
19.Remove fuel rail and injectors.
20.Remove 2 bolts securing fuel pressure regulator
to fuel rail.
21.Remove pressure regulator assembly.
22.Remove 'O' ring from fuel pressure regulator and
discard.
23.Remove 8 clips securing injectors to fuel rail.
24.Remove injectors from fuel rail.
25.Remove 2 'O' rings from each injector and
discard.Refit
26.Ensure mating surfaces between inlet manifold
and ram pipe housing are clean.
27.Ensure all locations in fuel rail and inlet manifold
are clean.
28.Lubricate and fit new 'O' rings to injectors and
fuel pressure regulator.
29.Fit fuel pressure regulator to fuel rail. Secure
with bolts. Tighten to
10 Nm.
30.Fit injectors to fuel rail. Secure with clips.
31.Position fuel rail to inlet manifold. Engage
injectors, one bank at a time.
32.Position ignition coil bracket on inlet manifold
studs.
33.Secure ignition coil bracket and fuel rail to inlet
manifold with nuts. Tighten to
8 Nm.
34.Remove plugs from fuel feed and return pipes
and rail.
35.Connect hose and tighten clip.
36.Clean feed pipe union and connect fuel feed
pipe to fuel rail. Tighten union to
16 Nm.
37.Connect multiplugs to fuel injectors and fuel
temperature sensor.
38.Remove cloth from inlet manifold.
39.Apply a thin, uniform coating of Loctite 577
sealant to mating face of inlet manifold.
40.Fit ram housing to inlet manifold. Secure with
bolts. Tighten to
24 Nm.
41.Connect purge hose, crankcase breather hose,
servo and pressure regulator vacuum hoses to
ram housing.
42.Fit plenum chamber.
See Plenum Chamber
43.Reconnect battery negative lead.
44.Start engine. Check for leaks around fuel rail and
injectors.