1998 JAGUAR X308 temperatur sensor

F
or evaporative emissions components,
REFER to: Evaporative Emissions
(30
3-13
Evaporative Emissions, Diagnosis and Testing).
For ECT sensor tests,
REFER to: Electronic Engine Controls
(30
3-14
Electronic Engine Co ntrols, Diagnosis and
Testing).
Engine stalls
soon after start
F
uel pump relay
ECM relay


Harness damage Fue

l pump
Engine coolan

t temperature
(ECT) sensor
Fue
l lines
F

uel pressure regulator
Air leakage


Check f
or DTCS. For fuel pump and ECM relay
tests,
REFER to: Fuel Charging and Controls
(30
3-04

Fuel Charging and Controls, Diagnosis and Testing).
Check fuel pressure.
REFER to: Fuel System Pressure Check
(31
0-
00 Fuel System - Genera l Information, General
Procedures).
For ECT sensor tests,
REFER to: Electronic Engine Controls
(30
3-14
Electronic Engine Co ntrols, Diagnosis and
Testing).
For fuel line information,
REFER to: Fuel Tank and Lines
(31
0-01 Fuel
Tank and Lines, Description and Operation).
For fuel pressure regulator,
REFER to: Fuel Charging and Controls
(30
3-04

Fuel Charging and Controls, Diagnosis and Testing).
For intake system information,
REFER to: Intake Air Distribution and Filtering

(30
3-12 Intake Air Distribution and Filtering,
Description and Operation).
Engine hesi
tates/poor acceleration
Fue
l pump
Air leakage


F

uel pressure regulator
Fue

l lines
Harness damage Throttl

e sensors
Throttl

e motor
Spark

plugs fouled, gapped
incorrectly
Ignition coil
failure(s)
Check f

or water ingress into
spark plug wells
HT sho
rt to ground (tracking)
check rubber boots for cracks/damage
Exhaus
t gas recirculation (EGR)

(SC only)
Chec
k fuel pressure,
REFER to: Fuel System Pressure Check
(31
0-
00 Fuel System - Genera l Information, General
Procedures).
For intake system information,
REFER to: Intake Air Distribution and Filtering

(30
3-12 Intake Air Distribution and Filtering,
Description and Operation). For fuel pressure regulator,
REFER to: Fuel Charging and Controls
(30
3-04

Fuel Charging and Controls, Diagnosis and Testing).
For fuel lines information,
REFER to: Fuel Tank and Lines
(31
0-01 Fuel
Tank and Lines, Description and Operation).
For throttle position se nsor and throttle motor
relay tests,
REFER to: Electronic Engine Controls
(30
3-14
Electronic Engine Co ntrols, Diagnosis and
Testing).
For spark plug tests, GO to Pinpoint Test B.
.
For ign
ition system tests, GO to Pinpoint Test
A.
. F
or EGR information,
REFER to: Engine Emission Control
(30
3-08
Engine Emission Cont rol, Description and
Operation).
Engine ba
ckfires
Fue
l pump
Fue

l lines
Air leakage


Mass ai

r flow (MAF) sensor
Spark plugs


Check f

or water ingress into
spark plug wells
HT sho
rt to ground (tracking)
check rubber boots for cracks/damage
Chec
k fuel pressure,
REFER to: Fuel System Pressure Check
(31
0-
00 Fuel System - Genera l Information, General
Procedures).
For fuel pump and lines,
REFER to: Fuel Tank and Lines
(31
0-01 Fuel
Tank and Lines, Description and Operation).
For intake system,
REFER to: Intake Air Distribution and Filtering

(30
3-12 Intake Air Distribution and Filtering,
Description and Operation). For MAF sensor tests,

Intake Air Distribution and Filtering - Intake Air Distribution and Filtering
Description an
d Operation
I

ntake Air Distribution and Filtering - Normally Aspirated Vehicles
Air Intake Asse
mbly

The air cleaner assembly consists of a two piece box containing the air filter, an airflow/temperature unit and the air intake
duct which connects to the top of the throttle assembly. The en gine full load breather feeds into the intake duct from the
bank 1 camshaft cover. A tuned stub on the ai r intake duct reduces the intake noise level.
Mass Air Flow and Temperature Sensors

The intake air is monitored by the Mass Air Flow (MAF) sensor assembly which is fitted at the outlet of the air filter
assembly. Two sensors are incorporated in the MAF sensor assembly, measuring air flow and temperature (temperature
sensor arrowed); both sensors provide anal ogue signal inputs to the engine control module (ECM) and are further described
in Section 303-14.

The air cleaner assembl y
consists of a tw
o piece box containing the ai r filter, an airflow/temperature unit (MAF sensor) and
the air intake duct which connects to the top of the throttle assembly. The engine full load breather feeds into the intake
duct from the bank 1 camshaft cover. Two tuned stubs on the air intake duct reduce the intake noise level.
Temperature Sensor

A second intake air temperature sensor (IAT sensor 2) is fitted at the outlet of the bank 1 charge air cooler. The sensor
provides an input to the ECM.
Air Intake Asse mbly

P a
rts List
It
e
m
Par
t
Number
De
scr
iption
1—Inta
k
e Air Temperature Sensor 2
2—Charge Air Cooler - Bank 1
3—Charge Air Cooler - Bank 2
4—Charge Air Cooler - Inlet Duct
5—Supercharger
Outlet D
uct
6—Supercharger
7—Supercharger
Pull
ey
8—Supercharger
Dri
ve Belt

Intake Air Distribution and Filtering - Charge Air Cooler RH
Remo
val and Installation
Remov
a
l
Installation
1. Disc onne
ct battery ground cable (IMPORTANT, see SRO
86.15.19 for further information).
2. Drain radiator coolant; refer to 26.10.01.
3. Remove air cleaner cover / intake assembly; refer to 19.10.30.
4. Remove throttle body; refer to 19.70.04.
5. Remove exhaust gas re-circulation valve (EGR) if installed;
refer to 17.45.01.
6. Remove throttle intake elbo w; refer to (SC) 19.70.28.
7. Remove supercharger outlet duct; refer to 18.50.16.
8. Remove coolant outlet pipe; refe r to operation (SC) 26.31.08.
9. Remove supercharger drive belt; refer to 18.50.08.
10. Remove supercharger; refer to operation 18.50.15.
11. Remove intake air temperatur e sensor 2 from charge air
cooler; refer to 18.30.52.
12. Detach engine harness retaining clip from rear of charge air
cooler.

13. Di
sconnect hoses from charge air cooler.
Pla

ce absorbent cloth in appropriate position.
Di
sc
onnect hoses.

14 . CAUTI
ON: Take care to avoi
d dropping any objects or
foreign matter into engine inle t duct with charge air cooler
removed.
Remove charge air cooler from the engine. 1. Remove eight bolts.
Remove charge air cooler.
2
. Discard gasket.
Cle
a
n all mating faces.
1.
Install ch arge air
cooler to adaptor.
1. Install new gasket.
2. Install charge air cooler.

Intake Air Distribution and Filtering - Charge Air Cooler Radiator
Remo
val and Installation
Remov
a
l
1.
Op
en the engine compartment and fit paintwork protection
sheets.
2. Disconnect the battery.
1. Remove the battery cover.
2. Disconnect the battery ground cable.
3. Remove the engine radiator and air conditioning condensor
assembly. Refer to operation 26.40.01.
4. Remove the grill assembly fo r access. Refer to operation
76.55.15.

5. Drain th e charge air cooler radiator.
Reach t
hrough the front bumper
splitter vane to remove
the radiator drain plug.

6. Disc
onnect the radiator
hoses from the radiator.
1. Disconnect the coolant pump to radiator hose.
2. Disconnect the return hose.
3. Disconnect the bleed pipe.

7. Re
move the two radiator fixing bolts.
8. Displace and re-position the am bient air temperature sensor
and bracket.

I
nstallation



9.
Di
splace the radiator from
the top mounting rubbers.
1. Fit and seat the radiator to the top mounting rubbers.

2. F
it the two securing bolts.
Ensure that the ambient air
temperature sensor mounting bracket is secured by the
lefthand radiator bolt.
3. Re-connect the radiator feed ho se, return hose and bleed pipe.
Fit all hose spring clips.
4. Refill the radiator coolant. Refer to operation 26.10.01.
5. Fit the grill assembly. Refer to operation 76.55.15.
6. Fit the engine radiator and air conditioning condensor
assembly. Refer to operation 26.40.01.
7. Reconnect the battery. Refer to the battery reconnection
procedure in 86.15.15.
8. Remove the paintwork protection sheets and close the engine
cover.

The E
VAP canister purge valve controls th
e flow rate of fuel vapour drawn into the engine during the canister purge
operation. The valve is opened by a vacu um feed from the induction elbow : the vacu um feed is controlled by the integral
valve solenoid and is applied when the so lenoid is energised. The solenoid is pulsed on (energised) and off by a fixed
frequency (100Hz) variable pulse width control signal (pulse width modulation). By varying the pulse on to off time, the
ECM controls the duty cycle of the valve (time that the valve is open to time closed) and thus the vapour flow rate to the
engine.
With no ECM signal applied to the va lve solenoid, the valve remains closed.
Can
ister Purge Operation
The
following pre-conditions are ne
cessary for purging to commence :
aft
er battery disconnection/reconnection, engine
management adaptations must be re-instated.
engine has run for
at least 8 seconds.
engi

ne coolant temperature is not less than 70 °C.
engine

not running in the fuel
cut off condition (eg overrun).
t
he adaptive fuel correction
function has not registered a rich or lean failure
t
he evaporative emission leak test has not failed
no faults have been diagnosted in th
e rel
evant sensor and valve circuits -
Air Flow Meter (AFM), Engine Coolant
Temperature sensor, Evaporativ e Canister Purge valve and Canister Close Valve (CCV).
If these conditions have been satisfied, purging is started. If any failures are registered, purging is inhibited.
The canister(s) is purged during each driv e cycle at various rates in accordance with the prevailing engine conditions. The
engine management software st ores a map of engine speed (RPM) against engine load (grams of air inducted / rev). For
any given engine speed and load, a vapour purge rate is assigned (purge rate increases with engine speed and load).
The preset purge rates are base d on the assumption of a vapour concentratio n of 100%. The actual amount of vapour is
measured by the closed loop fueling system : the input of evaporative fuel into the engine causes the outputs from the
upstream oxygen sensors to change, the am ount of change providing a measure of the vapour concentration. This feedback
causes the original purge rate to be adju sted and also reduces the amount of fuel input via the injectors to maintain the
correct air to fuel ratio.
Engine speed/load mapping and the corresp onding purge rates are different for single canister, running loss and ORVR
evaporative systems.