engine JAGUAR X308 1998 2.G Owners Manual

E
ngine Management System Components
Electronic Throt
tle
The
electronic throttle assembly, in resp
onse to signals from both the driver and the ECM, adjusts idle speed, sets the
throttle valve to the position requested by the driver's accelerator / throttle pedal, cruise and traction control, power
limitation and catalyst warm-up.
Mass
Air Flow Meter
The sensor i
s located in the air flow mete
r assembly and outputs an analogue voltag e to the ECM. This sensor measures air
flow into the engine inlet system and is calibrated to measure kg / hour.
In
take Air Temperature
Th
e intake air temperature sensor is loca
ted in the air flow meter assembly and outputs an analogue voltage to the ECM.
The ECM will substitute a default value eq ual to 50°C should this sensor fail.
Fuel Injectors
The eigh
t bottom fed fuel injectors are located in the fuel rails. Th
e fuel injectors are electromagnetic solenoid valves
controlled by the ECM. The pulse time for the injector combined with the fuel pr essure determines the volume of fuel
injected to the manifold.
Fue
l Delivery
The fu
el pump provides fuel to the fuel rail where the circulat
ing pressure is controlled by a pressure regulator valve; excess
fuel is returned to the fuel tank.
The pressure regulator valve is controlled by manifold depression so that fuel delivery pressure is maintained at
approximately 3 bar above manifold pressure.
Fuel Pump
Relay
The ECM controls thi

s component for normal
engine running. The security system may disable this relay via communication
with the ECM.
Fuel Lev
el Sensing
The tank fuel

is measured by the fuel le
vel sensor . This signal is used by the ECM as an in put to certain diagnostics.
Eva
porative Valve
Excess vapour

formed in the fuel tank is
absorbed into the evaporative emission pu rge control canister. While the engine is
running, the fuel absorbed in the canister is gradually purged back into the engine. The rate of purging is governed by
engine operating conditions and vapour concentration level. Operating conditions which affect the purge rate are:
2—Purge
valve
3—Engine

torque reduction
4—E

lectronic throttle assembly
5—Coo

ling fans
6—Ignition amplifier driver
7—Engine overspeed
8—Cli

mate control compressor clutch
9—O

BDII information (J1962, CAN, ISO)

10—F
uel pump relay
11—Heat

ed oxygen sensor
12—Vari

able valve timing
13—MIL sw

itching



ECM Out
puts
It

em
Par
t Number
De
scription
1—Exhaus

t gas recirculation

Speed an
d load
Coo
l
ant temperature
Ti
me el
apsed from start up
Cl
osed l
oop fuelling
Determination of the vapour concentration is made by stepped opening of the EVAP valve and subsequent monitoring of the
fuelling correction. This function is performed prior to purging, so that at the onse t of purging the EVAP valve can be set to
the optimum position. Should the ECM be unable to determine the concentration before purging, a default value is
employed, which is then modified whilst purging is in progress.
When the purging process is operational th e ECM modifies the basic fuelling calculation to maintain the correct air / fuel
ratio.
Purging is inhibited during fuel cut-off and stability / traction control intervention.
Coolant Temperature Sen
sor
Th
e
sensor outputs a voltage to the ECM which decreases as temperature increases.
Cooling Fans


In response to engi
ne coolant temperat
u
re and climate control system demand, the ECM will energize the cooling fans.
Climate Control Compressor
The E
C
M will allow the compressor clutch to be engaged if th
e engine temperature and load demand are normal. Should the
driver require maximum engine powe r or the coolant temperature be high, the request will be denied.
Cranking Signal

The ECM reacts to a signal fr
om th
e Body Processor Module (BPM) when the starter motor relay is energi
zed. This signal is
used to trigger starting, fu el and ignition strategies.
Engine Speed and Cranksh
aft Position
Engine
speed and cran
k position are moni
tored by a sensor which is mounted on the cylinder block (flywheel housing)
behind the crankshaft drive plat e. It indicates rotational speed to the ECM in the form of 12 pulses per crank revolution.
Engine speed is used for synchronization of fuel an d ignition systems, as well as other functions.
Camshaft Position
The ca
mshaft position sensor is mounted at
the rear of Bank 2 cylinder head on the inlet side and provides one signal every
720 degrees of crankshaft rotation. The signal, in conjunction with the signal from the crankshaft position sensor, indicates
to the ECM that the piston of cylinder 1A is approaching TDC on the compression stroke.
Variable Valve
Timing (Where Fitted)
By energi
si
ng a solenoid to allow the pass
age of pressurized oil on each of the inle t camshaft drives, the ECM can vary by a
single stepped amount, the relati ve timing of the inlet valves.
Ign
ition
Ignit
i
on spark is produced by
individual on-plug coil units.
There are two ignition amplifiers; module #1 drives coils 1A, 2B, 3B and 4A, whilst module #2 drives coils 1B, 2A, 3A and
4B. The ECM controls the amplifiers.

Thi
s sensor uses a piezo-electric sensing element to detect kn
ock which may occur under acceleration at critical conditions.
Should detonation be present the ECM will retard ignition timing of individual cylinders.
Exhaust G
as Recirculation
The EGR
valve (where fitted) reduces NOx
emissions by recirculating a portion of the exhaust gases back into the inlet
manifold.
Heated Oxyg
en Sensors
The h
eated oxygen sensors, one per bank, are situated upstream of the catalysts. Integral
to the sensors are heaters
(under ECM control) which allow the sensor s to reach their operating temperature as soon as possible after engine start. A
comparison between the level of oxygen in the exhaust gas to that in the atmosphere produces an output signal. This signal
is used by the engine closed loop fuel strategy to make fuelling corrections and so control overall emission levels.
Oxygen Sensors

Thes
e sensors, one per bank, are situated downstream of the
catalyst. The comparison of upstream and downstream signals
allows determination of cata lyst conversion efficiency.




Knock Sensor

En
gine - Engine
D
iagnosis and Testing
Sym

ptom Chart
Sy
mptom Chart
Pinp

oint test A: P1392 (P1397)
VVT solenoid circuit low input
S
pecial Tool(s)

D

igital multimeter

Generi

c scan tool
Sy

mptom
Possib
le Sources
Acti
on
D

TC P1392 VVT solenoid A circuit low input
So
lenoid coil open circuit
Harness open circuit or blown fuse
Connector pins(s) bent , loose or corroded
*
*
*
GO to
P
inpoint Test A

*
D
TC P1397 VVT solenoid B circuit low input
So
lenoid coil open circuit
Harness open circuit or blown fuse
Connector pins(s) bent , loose or corroded
*
*
*
GO to
P
inpoint Test A

*
D
TC P1393 VVT solenoid A circuit high input
So
lenoid coil short circuit
Harness short circuit
Connector pins(s) bent , loose or corroded
*
*
*
GO to
P
inpoint Test B

*
D
TC P1398 VVT solenoid B circuit high input
So
lenoid coil short circuit
Harness short circuit
Connector pins(s) bent , loose or corroded
*
*
*
GO to
P
inpoint Test B

*
D
TC P1396 VVT solenoid B malfunction
O
il pressure failure
VVT solenoid sticking
Connector pins(s) bent , loose or corroded
Crankshaft position sensor failure
ECM failure
*
*
*
*
*
GO to
P
inpoint Test C

*
P
INPOINT TEST A : P1392 (P1397) VVT SOLENOID CIRCUIT LOW INPUT
•
NOTE: References in brac
kets are for Bank B (2)
T
EST CONDITIONS
D
ETAILS/RESULTS/ACTIONS
A1

: RETRIEVE DTCS
•

NOTE: Battery and or ECM disconnection prior to scanning wi
ll erase all data, ensure that the correct DTC is present.

En
gine - Valve Clea
rance Adjustment
Gene
ral Procedures
S
p
ecial Tool(s)

Tappet adjustment
3
03-
540

Ai
r gun, fan nozzl
e
303-590
1. Open the engine compartment and fit paintwork protection
sheets. Open to the service position.
2. Carefully remove both engine covers, taking care not to
damage the plasti c fixings or the rubber inserts.

3. Disc
onnect the batt
ery ground cable.
Re
move the battery cover.
4. Remove the cam cover from the 'A' bank and the 'B' bank;
including the purge valve, the on-plug ignition coils and the air
intake tube / air flow meter / air cleaner cover assembly. Refer
to Operations 12.29.43 and 12.29.44.
5. Check, and note the valve cleara nces, as described earlier in
this section.
6. Use a rag to wipe up as much oil as possible from the tappet
wells.
7. Valve adjustment involves considerable repetition. A SUMMARY
OF THE PROCEDURE follows:
1. Fit the adjusting tool base plate to one cylinder head.
2. Rotate the crankshaft to position four valves ready for
adjustment.
3. Use the attachment part of the special tool to adjust two valve clearances. Transfer the attachment and
adjust the other two valve clearances.
4. Remove the attachment pa rt from the adjusting tool
base plate.

5.
Repeat steps 2 to 4 three
more times until all sixteen
valves on the first cylinder head have been adjusted.
6. Repeat steps 1 to 5 for the other cylinder head.
7. Remove all equipment and reassemble the engine.
8. The following instructions describe the PROCEDURE FOR
ADJUSTING THE VALVE CLEARANCES.

9. F
it the base plate of the tappet
adjusting tool 303 - 540 to one
of the heads; use the bolts which are supplied with the tool.
It
should be fitted along the head, between the two
camshafts, and bolted to the tapped holes which normally
secure the cam cover.
10. Rotate the crankshaft so that there are four valves which are
'off the cam'(cam lobes uppermos t), so that their clearance
may be measured.

11
.
CAUTION: Do not rotate the crankshaft while the
attachment is fitted to the base plate.
Fit the attachment of 303 - 540 to the base plate. 1. Set the fingers of the attachment to the highest position (unscrew the knurled bolts).
2. Fit the attachment to the base plate, adjacent to the first two valves to be adjusted.
3. Tighten the screws to secure the attachment to the base plate.

12
.
Position the fingers on to the outer edges of the tappet. It is
essential that the recessed step on each finger, locates on the
edge of the tappet as indicated. The use of a mirror will help,
as viewing access is restricted.

13
.
Tighten the knurled bolts to compress the valve springs, until
a firm resistan ce is felt.

14
. WARNING: TH
E FOLLOWING OPERATIONS REQUIRE
THE USE OF COMPRESSED AIR - ALWAYS WEAR SUITABLE EYE
PROTECTION.
Remove, clean and measure the shims.
1. Surround the immediate wo rking area with clean rag
to contain any loose objects and shims displaced by
the compressed air.
2. Use 303 - 590 Air Gun (with a fan nozzle) aimed at the edge of the shim to lift it from the tappet.
Remove the shim from each tappet, noting the
position of each.
15 . Cl
ean and measure the thickness of each shim.
16. Assess the increase or decrease required in shim thickness to
produce the correct valve clearance.
17. Select two shims of the correct size, lubricate each and fit
each to the respective tappet (as calculated in the previous
step). Shims must be fitted with the size marking facing the
tappet NOT the cam.

18 . Loos
en the knurled screws on 303 - 540 attachment to allow
the valve springs to return to their normal position.
19. Check the valve clearance of the two valves. If the clearance
is correct, remove the attachment from the base plate. transfer
the attachment to the other two valves which are in position to
be adjusted.
20. Repeat the adjustment procedure, as described in the
Summary.
21. Refit the cam covers and associated components. Refer to
Operations 12.29.43 and 12.29.44.
22. Refit the engine covers.
23. Check the engine oil level; rectify as necessary.
24. Move the engine compartment cover from the service position
and connect the gas struts.
25. Remove the paint protection sheets and close the cover.
26. Connect the battery and fit the battery cover.
Refe
r to the Battery Reconnection Procedure 86.15.15.

E
ngine - Valve Clearance Check
Gen
eral Procedures

1.
Open the engine compartment and fit paintwork protection
sheets. Open to the service position.
2. Carefully remove both engine covers, taking care not to
damage the plasti c fixings or the rubber inserts.

3. Di
sconnect the batt
ery ground cable.
R
emove the battery cover.
4. Remove the cam cover from the 'A' bank and the 'B' bank;
including the purge valve, the on-plug ignition coils and the air
intake tube / air flow meter / air cleaner cover assembly. Refer
to Operations 12.29.43 and 12.29.44.
5. Rotate the crankshaft so that there are four valves which are
'off the cam' (cam lobes upperm ost), so that their clearance
may be measured.
6. Measure the gap on each of the four valves. Note which valve
has been measured, along with its relevant clearance.
7. Rotate the crankshaft a small am ount so that the next four
valves are 'off the cam'. Measure and note the clearances.
Re
peat this step
a further six times, until all valve
clearances have been measured and noted.
8. Refit the cam covers and associated components. Refer to
Operations 12.29.43 and 12.29.44.
9. Refit the engine covers.
10. Move the engine compartment cover from the service position
and connect the gas struts.
11. Remove the paint protection sheets and close the cover.
12. Connect the battery and fit the battery cover.
Re
fer to the Battery Reconnection Procedure 86.15.15

Engine - Connecting Rod Bearings
In-vehic
le Repair
Remov
a
l

1.
Disc
onnect the batt
ery ground cable.
Re
move the battery cover.
2. Open the engine compartment and fit paintwork protection
sheets.
3. Remove the engine compartmen t cover. Refer to operation
76.16.01.
4. Remove the twin fan and motor assembly. Refer to Operation
26.25.12.
5. Remove the timing cover and al l associated components, as
detailed in Operation 12.65.01.
6. Remove both front wheel and tyre assemblies. Refer to
Operation 74.20.05.
7. Remove the undertray. Re fer to Operation 76.22.90.
8. Remove the front crossmember fo r access. Refer to Operation
76.10.05.

9. Drai
n the engine oil.
1. Position the waste oil bowser.
2. Remove the drain plug from the oil pan and drain the engine oil.
Install a new sealing wash er to the
drain plug.
Wipe the drain plug an
d
install
it to the oil pan to prevent
oil dripping.
Move the oil bowser away f
rom the vehicle.

10 . Re
move the oil pan.
1. Remove the eighteen bolt s which secure the oil pan
to the oil pan body.
2. Remove the oil pan.
3. Remove the gasket from the oil pan body assembly.
11. Remove the oil pan body a ssembly. Refer to Operation

20. Apply new en
gine oil to the co
nnecting rod bearing and to the
crankpin.

21. Carefull
y move the connecting
rod and piston assembly
towards the the crankshaft and connect it to the crankpin.
Rotate the crankshaft slightly if necessary.
22. If necessary, refer to the Spec ification Section for details of
piston and connecting rod orientation.

23 . Install and alig
n the new bearin
g shell to the connecting rod
cap.
24. Apply new engine oil to the bearing shell.

25 . Install th
e cap and NEW bolts to the connecting rod.
1. Note the position of the identification marks and install the cap so that the identification marks are
adjacent to those on the connecting rod.
2. Install the new bolts whic h secure the bearing cap.
26. Tighten the bolts as follows: