1998 JAGUAR X308 sensor

generates a signal when th
e dr
ive plate passes the sensor
sen
ds the ECM signals indicating crankshaft position and engine speed
is e

ssential for calculating spark timing
En

gine Coolant Temperature (ECT) Sensor
sen
ds the ECM a signal indicating the temperature of the engine coolant
is a t

emperature dependent resistor with a negative temperature coefficient (resistance changes inversely with
respect to temperature) and is constantly monitored by the ECM
Intake Air Temperature (IAT) Sensor

is m
ounted in the same housing as the MA
F sensor but is not a serviceable item
sen
ds the ECM a signal indicating the temperature of the air entering the engine
is a t

emperature dependent resistor which has a negative
temperature coefficient (its resistance changes inversely
with respect to ambient temperature).
Knock S
ensor (KS)
is a pi
ezo-electric device which sends a signal
to the ECM indicating engine detonation
Between 700 and 6800 rpm, the ECM will retard individual cylinder ignition timing when detonation occurs while allowing
the other cylinders to continue operating normally.
During acceleration, at critical load and speed conditions, the ECM retards ignition timing to prevent the onset of detonation.
H
eated Oxygen Sensor (HO2S)
are
positioned upstream of the catalytic convertor
is equipped with

a heating element wh
ich improves the response time of the sensors during engine warm-up
h
as the ability to generate a voltage signal proportional to the oxygen content of the exhaust gases leaving the
engine
pr
ovides feedback information to the ECM used to calc
ulate fuel delivery and provide optimum gas emissions
Variable V
alve Timing (VVT) Solenoid
R
efer to section 303-01.

is
of the 'hot-wire' type (the resistan
ce of the wire varies as incoming air passing over it has a cooling effect)
provides f
eedback to the ECM to perm
it monitoring of mass air flow
is NO
T serviceable, necessitating its renewal should a fault occur
Mass Air Flo
w (MAF) Sensor
Location

P
arts List
It

em
Par
t Number
De
scription
1—PI032

VVT solenoid 2
2—PI027

KS 2
3—PI004

ECT sensor
4—PI026

KS 1
5—PI031

VVT solenoid 1
6—PI035

MAFS (on vehicle)
7—PI050

Generator
8—PI040

Oil pressure switch
9—PI018

to PI021 Bank 1 Ignition coils 1 to 4
PI022 to PI025 Bank 2 Ignition coils 1 to 4
10—PI006
Throttle valve position sensor
11—PI002 En

gine management harness (on vehicle)
12—PI001 En

gine management harness (on vehicle)
13—PI033

Throttle valve motor
14—PI034

EGR valve (where fitted)
15—PI015 CM

P sensor
16—PI042

Accelerator pedal and
mechanical guard sensors
17—PI007
to PI010 Bank 1 Injectors 1 to 4 PI011 to PI014 Bank 2 Injectors 1 to 4
18—PI037

Compressor lock
sensor (where fitted)
19—PI036
Compressor clutch
20—PI017 CK

P sensor
E
ngine Harness Connectors
Location

It
em
De
scription
1Mechanica

l guard
position sensor (potentiometer)
2Pedal demand sensors (pot
entiometers)
3Thro

ttle position sensor
4Engine

control
module (ECM)
5Throttl
e motor power relay
6EMS fuse box
7Throttl

e motor
T
hrottle Sensors and Control

Ite
m
Part
Number
Descr
iption
1—Knock
sensors, banks 1 and 2

2—Engine
control module (E
CM)
Knock
Sensor

It
em
Par
t Number
De
scription
1—Cranksh

aft position sensor
2—Engine

control module (ECM)
Crankshaft Posi
tion sensor

Ite
m
Par
t
Number
De
scr
iption
1—Camshaft position

sensor
2—Engine
control module (E
CM)
Cams
haft
Position sensor

It
em
Par
t Number
De
scription
1—MAF

assembly
2—MAF s

ensor
3—IAT se

nsor
4—Engi

ne to vehicle harness connector
5—EMS fuse box


6—Engine

control module (ECM)
7—Charge air cool

er -
IAT sensor (superchar
ged engin
es only)

MAF
and IAT Sensors