(5) Slide exhaust manifold and turbocharger on
exhaust manifold studs (Fig. 17).
(6) Install exhaust manifold retaining nuts. Torque
nuts to 32.4N´m.
(7) Install exhaust manifold heat shield (Fig. 17).
Torque bolts to 27.5N´m.
(8) Install turbocharger outlet to charge air cooler
pipe (Fig. 16).
(9) Install thermostat housing to upper radiator
hose pipe (Fig. 16). Install retaining bolt and torque
to 47.1N´m.
(10) Install coolant recovery pressure container
(Refer to 7 - COOLING/ENGINE/COOLANT RECOV-
ERY PRESS CONTAINER - INSTALLATION).
(11) Connect glow plug and coolant temperature
sensor electrical connectors.
(12) Install new cylinder head cover/intake mani-
fold gasket.
(13) Install rocker arm and lifter assemblies.Be
sure to put rocker arm and lifter assemblies in
same location as removed.
(14) Install cylinder head cover/intake manifold
(Fig. 15)(Refer to 9 - ENGINE/CYLINDER HEAD/
CYLINDER HEAD COVER(S) - INSTALLATION).
(15) Install timing belt inner cover (Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - INSTALLATION).
(16) Install timing belt (Refer to 9 - ENGINE/
VALVE TIMING/TIMING BELT/CHAIN AND
SPROCKETS - INSTALLATION) .
(17) Install timing belt outer cover (Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - INSTALLATION).
(18)Remove crankshaft and both camshaft
locking pins at this time(Refer to 9 - ENGINE/
VALVE TIMING - STANDARD PROCEDURE).
(19) Install generator (Refer to 8 - ELECTRICAL/
CHARGING/GENERATOR - INSTALLATION).
(20) Install accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
INSTALLATION).
(21) Install power steering belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
INSTALLATION).
(22) Install right engine mount (Refer to 9 -
ENGINE/ENGINE MOUNTING/RIGHT MOUNT -
INSTALLATION).
(23) Install air cleaner housing assembly.
(24) Refill cooling system (Refer to 7 - COOLING/
ENGINE/COOLANT - STANDARD PROCEDURE).
(25) Install engine cover (Refer to 9 - ENGINE -
INSTALLATION).
(26) Install front wiper unit (Refer to 8 - ELEC-
TRICAL/WIPERS/WASHERS/WIPER MODULE -
INSTALLATION).
(27) Connect negative battery cable.CAMSHAFT(S)
DESCRIPTION
The camshafts are made of gray cast iron with
eight machined lobes and four bearing journals (Fig.
20).
OPERATION
When the camshaft rotates the lobes actuate the
hydraulic lifters and rocker arms, forcing downward
on the rocker arms which opens the valves.
REMOVAL
(1) Disconnect negative battery cable.
(2) Remove front wiper unit (Refer to 8 - ELEC-
TRICAL/WIPERS/WASHERS/WIPER MODULE -
REMOVAL).
(3) Remove engine cover (Refer to 9 - ENGINE -
REMOVAL).
(4) Drain cooling system (Refer to 7 - COOLING/
ENGINE/COOLANT - STANDARD PROCEDURE).
(5) Remove air cleaner housing.
(6) Remove power steering belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL).
(7) Remove accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL).
(8) Remove generator (Refer to 8 - ELECTRICAL/
CHARGING/GENERATOR - REMOVAL).
(9) Support engine and remove right engine mount
(Refer to 9 - ENGINE/ENGINE MOUNTING/RIGHT
MOUNT - REMOVAL).
Fig. 20 CAMSHAFTS
1 - INTAKE CAMSHAFT
2 - EXHAUST CAMSHAFT
9a - 22 ENGINERG
CYLINDER HEAD (Continued)
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CAUTION: Before removing the cylinder head cover/
intake manifold or timing belt the engine must put
at 90É after TDC. Failure to do so could result in
valve and/or piston damage during reassembly.
(Refer to 9 - ENGINE/VALVE TIMING - STANDARD
PROCEDURE)
(10) Remove timing belt outer cover (Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - REMOVAL).
(11) Remove timing belt (Refer to 9 - ENGINE/
VALVE TIMING/TIMING BELT/CHAIN AND
SPROCKETS - REMOVAL).
(12) Remove timing belt inner cover (Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - REMOVAL).
(13) Remove cylinder head cover/intake manifold
(Refer to 9 - ENGINE/CYLINDER HEAD/CYLIN-
DER HEAD COVER(S) - REMOVAL).
(14) With cylinder head cover/intake manifold on
work bench, remove plugs at rear of cylinder head
cover/intake manifold.
(15) Remove camshaft oil seals (Fig. 21).
(16) Remove snapring and thrust washer from
camshaft (Fig. 21).
(17) Slide camshaft through access hole at rear of
cylinder head cover/intake manifold.
INSTALLATION
(1) Lubricate the camshafts with MopartEngine
Oil Supplement, or equivalent.
(2) Carefully install camshafts into access holes in
rear of cylinder head cover/intake manifold.
(3) Install thrust washer, snapring, and camshaft
oil seal (Fig. 21).
CHECKING CAMSHAFT ENDPLAY
(1) After camshafts are properly installed in cylin-
der head cover check end play of camshafts with a
dial indicator. The end play should be between .10
mm ± .30 mm.
NOTE: If the camshaft endplay is not within speci-
fication, measure thickness of the camshaft spacer.
Camshaft spacer thickness should be 2.8 .02mm.
(4) Install access hole plugs and gaskets at rear of
cylinder head cover/intake manifold. Torque plugs to
80N´m.
(5) Install cylinder head cover/intake manifold on
engine block (Refer to 9 - ENGINE/CYLINDER
HEAD/CYLINDER HEAD COVER(S) - INSTALLA-
TION).
(6) Install timing belt inner cover (Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - INSTALLATION).(7) Install timing belt (Refer to 9 - ENGINE/
VALVE TIMING/TIMING BELT/CHAIN AND
SPROCKETS - INSTALLATION) .
(8) Install timing belt outer cover (Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - INSTALLATION).
(9) Install right engine mount (Refer to 9 -
ENGINE/ENGINE MOUNTING/RIGHT MOUNT -
INSTALLATION).
(10) Install generator (Refer to 8 - ELECTRICAL/
CHARGING/GENERATOR - INSTALLATION).
(11) Install accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
INSTALLATION).
(12) Install power steering belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
INSTALLATION).
(13) Install air cleaner housing.
(14) Refill cooling system (Refer to 7 - COOLING/
ENGINE/COOLANT - STANDARD PROCEDURE).
(15) Install front wiper unit (Refer to 8 - ELEC-
TRICAL/WIPERS/WASHERS/WIPER MODULE -
INSTALLATION).
(16) Connect negative battery cable.
Fig. 21 CAMSHAFT ASSEMBLY
1 - INTAKE CAMSHAFT
2 - SNAPRING
3 - CAMSHAFT OIL SEAL
4 - THRUST WASHER
5 - CYLINDER HEAD COVER/INTAKE MANIFOLD
6 - EXHAUST CAMSHAFT
RGENGINE9a-23
CAMSHAFT(S) (Continued)
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CYLINDER HEAD COVER(S)
DESCRIPTION
The cylinder head cover is made of cast aluminum
and is also the intake manifold on this engine (Fig.
22).
REMOVAL
CAUTION: Before removing the cylinder head cover/
intake manifold the engine must put at 90É after
TDC. Failure to do so could result in valve and/or
piston damage during reassembly. (Refer to 9 -
ENGINE/VALVE TIMING - STANDARD PROCEDURE)
(1) Disconnect negative battery cable.
(2) Remove front wiper unit (Refer to 8 - ELEC-
TRICAL/WIPERS/WASHERS/WIPER MODULE -
REMOVAL).
(3) Remove engine cover (Refer to 9 - ENGINE -
REMOVAL).
(4) Drain cooling system (Refer to 7 - COOLING/
ENGINE/COOLANT - STANDARD PROCEDURE).
(5) Rotate engine until 90É after TDC is reached.
Install both camshaft locking pins and the crankshaft
locking pin. (Refer to 9 - ENGINE/VALVE TIMING -
STANDARD PROCEDURE)
(6) Remove air cleaner housing assembly.
(7) Remove power steering belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL).(8) Remove accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL).
(9) Remove generator (Refer to 8 - ELECTRICAL/
CHARGING/GENERATOR - REMOVAL).
(10) Support engine and remove right engine
mount (Refer to 9 - ENGINE/ENGINE MOUNTING/
RIGHT MOUNT - REMOVAL).
(11) Remove outer timing belt cover (Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - REMOVAL).
(12) Remove timing belt (Refer to 9 - ENGINE/
VALVE TIMING/TIMING BELT/CHAIN AND
SPROCKETS - REMOVAL).
(13) Remove inner timing belt cover (Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - REMOVAL).
(14) Disconnect camshaft position sensor, boost
pressure/intake air temperature sensor, EGR sole-
noid, and fuel pressure sensor electrical connectors
(Fig. 23).
Fig. 22 CYLINDER HEAD COVER/INTAKE
MANIFOLD
Fig. 23 ENGINE COMPONENT LOCATIONS
1 - FUEL INJECTOR RETURN LINE
2 - FUEL INJECTOR SUPPLY LINE
3 - OIL SEPARATOR
4 - FUEL INJECTOR
5 - CAMSHAFT POSITION SENSOR
6 - BOOST PRESSURE/INTAKE AIR TEMPERATURE SENSOR
7 - EGR SOLENOID
8 - FUEL PRESSURE SENSOR
9 - CYLINDER HEAD COVER/INTAKE MANIFOL
10 - FUEL RAIL
11 - WIRING HARNESS RETAINING CLIPS
9a - 24 ENGINERG
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(22) Install right engine mount (Refer to 9 -
ENGINE/ENGINE MOUNTING/RIGHT MOUNT -
INSTALLATION).
(23) Install generator (Refer to 8 - ELECTRICAL/
CHARGING/GENERATOR - INSTALLATION).
(24) Install accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
INSTALLATION).
(25) Install power steering belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
INSTALLATION).
(26) Install air cleaner housing assembly.
(27) Remove crankshaft and both camshaft locking
pins (Refer to 9 - ENGINE/VALVE TIMING - STAN-
DARD PROCEDURE).
(28) Refill cooling system (Refer to 7 - COOLING/
ENGINE/COOLANT - STANDARD PROCEDURE).
(29) Install engine cover (Refer to 9 - ENGINE -
INSTALLATION).
(30) Install front wiper unit (Refer to 8 - ELEC-
TRICAL/WIPERS/WASHERS/WIPER MODULE -
INSTALLATION).
(31) Connect negative battery cable.
CAMSHAFT OIL SEAL(S)
REMOVAL
(1) Disconnect negative battery cable.
(2) Remove air cleaner housing assembly.
(3) Support engine and remove right engine mount
(Refer to 9 - ENGINE/ENGINE MOUNTING/RIGHT
MOUNT - REMOVAL).
(4) Remove outer timing belt cover (Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - REMOVAL).
WARNING: Before removing the timing belt the
engine must put at 90É after TDC. Failure to do so
could result in valve and/or piston damage during
reassembly. (Refer to 9 - ENGINE/VALVE TIMING -
STANDARD PROCEDURE)
(5) Remove timing belt (Refer to 9 - ENGINE/
VALVE TIMING/TIMING BELT/CHAIN AND
SPROCKETS - REMOVAL).
(6) Using VM.1055, remove both camshaft gears
(Fig. 28).
(7) Remove both camshaft oil seals.
INSTALLATION
(1) Install new camshaft oil seal using VM.1057.
(2) Install camshaft sprockets and tighten retain-
ing bolts finger tight.
(3) Install timing belt (Refer to 9 - ENGINE/
VALVE TIMING/TIMING BELT/CHAIN AND
SPROCKETS - INSTALLATION) .(4) Torque camshaft sprockets to 108 N´m using
VM.1055 (Fig. 28).
(5) Install outer timing belt cover (Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - INSTALLATION).
(6) Install right engine mount (Refer to 9 -
ENGINE/ENGINE MOUNTING/RIGHT MOUNT -
INSTALLATION).
(7) Install air cleaner housing assembly.
(8) Connect negative battery cable.
ROCKER ARMS
DESCRIPTION
The rocker arms are made of stamped steel (Fig.
29).
OPERATION
The rocker arms are used as a link between the
camshaft and valves. As the camshaft rotates the
lobes of the camshafts apply downward pressure on
the rocker arms. This pressure is then transmitted to
the valves which causes the valves to open.
REMOVAL
(1) Disconnect negative battery cable.
Fig. 28 CAMSHAFT GEAR REMOVAL/INSTALLATION
1 - TIMING BELT INNER COVER
2 - CAMSHAFT SPROCKET
3 - IDLER PULLEYS
4 - CAMSHAFT SPROCKET
5 - VM.1055
RGENGINE9a-27
CYLINDER HEAD COVER(S) (Continued)
ProCarManuals.com
VALVE TIMING
STANDARD PROCEDURE - LOCKING ENGINE
90É AFTER TDC
(1) Disconnect negative battery cable.
(2) Remove starter motor (Refer to 8 - ELECTRI-
CAL/STARTING/STARTER MOTOR - REMOVAL).
(3) Rotate engine untill notch in hub is in the fol-
lowing position (Fig. 84).
(4) Special tool VM.1068 can be install in engine
block as shown at this time (Fig. 85). This will lock
the engine at 90É after TDC.
(5) Remove front wiper unit (Refer to 8 - ELEC-
TRICAL/WIPERS/WASHERS/WIPER MODULE -
REMOVAL).
(6) Remove engine cover (Refer to 9 - ENGINE -
REMOVAL).
(7) Remove plug in cylinder head cover/intake
manifold and insert VM.1053 to lock exhaust cam-
shaft in position (Fig. 86).
(8) Remove generator (Refer to 8 - ELECTRICAL/
CHARGING/GENERATOR - REMOVAL).
Fig. 84 CRANKSHAFT HUB ALIGNMENT
1 - VIBRATION DAMPER/CRANKSHAFT PULLEY
2 - CRANKSHAFT HUB NOTCH
3 - VIBRATION DAMPER/CRANKSHAFT PULLEY TO
CRANKSHAFT HUB BOLTS
Fig. 85 TDC AND 90 DEGREES AFTER TDC
ALIGNMENT PIN LOCATION
1 - ENGINE BLOCK
2 - VM.1051 TDC PIN OR VM.1068 90 DEGREES ATDC PIN
3 - FLYWHEEL
Fig. 86 EXHAUST CAMSHAFT LOCKING PIN
VM.1053
1 - EXHAUST MANIFOLD HEAT SHIELD
2 - EXHAUST CAMSHAFT LOCKING PIN VM.1053
3 - COOLANT TUBE FROM THERMOSTAT HOUSING TO UPPER
RADIATOR HOSE
4 - CYLINDER HEAD COVER/INTAKE MANIFOLD
RGENGINE9a-53
ProCarManuals.com
(9) Remove plug in cylinder head cover/intake
manifold and insert VM.1052 to lock intake camshaft
in position (Fig. 87).
(10) At this point the timing belt can be removed
for service.
(11) After engine service is completed and timing
belt reinstalled, remove both camshaft locking pins
from cylinder head cover/intake manifold.
(12) Install both camshaft access plugs.
(13) Remove 90É after TDC engine locking pin.
(14) Install starter motor (Refer to 8 - ELECTRI-
CAL/STARTING/STARTER MOTOR - INSTALLA-
TION).
(15) Install generator (Refer to 8 - ELECTRICAL/
CHARGING/GENERATOR - INSTALLATION).
(16) Install engine cover (Refer to 9 - ENGINE -
INSTALLATION).
(17) Install front wiper unit (Refer to 8 - ELEC-
TRICAL/WIPERS/WASHERS/WIPER MODULE -
INSTALLATION).
(18) Connect negative battery cable.BALANCE SHAFT
DESCRIPTION
The 2.5L Common Rail Diesel engine is equipped
with two nodular cast iron balance shafts in a cast
aluminum carrier. The balance shaft assembly is
mounted to the engine block (Fig. 88).
OPERATION
The balance shaft is driven by the crankshaft. The
balance shafts are connected by heelical gears. The
dual-counter rotating shafts decrease second order
vertical shaking forces caused by component move-
ment.
Fig. 87 INTAKE CAMSHAFT LOCKING PIN VM.1052
1 - TIMING BELT INNER COVER
2 - GLOW PLUG ELECTRICAL CONNECTOR
3 - CYLINDER HEAD COVER/INTAKE MANIFOLD
4 - FUEL RAIL
5 - INTAKE CAMSHAFT LOCKING PIN VM.1052
Fig. 88 BALANCE SHAFT ASSEMBLY
1 - BALANCE SHAFT
2 - OIL JET RETAINING BOLT
3 - OIL JET
4 - ENGINE BLOCK
5 - CRANKSHAFT
6 - BALANCE SHAFT RETAINING BOLTS
7 - OIL DIPSTICK TUBE RETAINER
8 - RUBBER BUSHING
9 - RETAINING BOLT
9a - 54 ENGINERG
VALVE TIMING (Continued)
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FUEL INJECTION
OPERATION
OPERATION - INJECTION SYSTEM
All engines used in this section have a sequential
Multi-Port Electronic Fuel Injection system. The MPI
system is computer regulated and provides precise
air/fuel ratios for all driving conditions. The Power-
train Control Module (PCM) operates the fuel injec-
tion system.
The PCM regulates:
²Ignition timing
²Air/fuel ratio
²Emission control devices
²Cooling fan
²Charging system
²Idle speed
²Vehicle speed control
Various sensors provide the inputs necessary for
the PCM to correctly operate these systems. In addi-
tion to the sensors, various switches also provide
inputs to the PCM.
The PCM can adapt its programming to meet
changing operating conditions.
Fuel is injected into the intake port above the
intake valve in precise metered amounts through
electrically operated injectors. The PCM fires the
injectors in a specific sequence. Under most operat-
ing conditions, the PCM maintains an air fuel ratio
of 14.7 parts air to 1 part fuel by constantly adjust-
ing injector pulse width. Injector pulse width is the
length of time the injector is open.
The PCM adjusts injector pulse width by opening
and closing the ground path to the injector. Engine
RPM (speed) and manifold absolute pressure (air
density) are theprimaryinputs that determine
injector pulse width.
OPERATION - MODES OF OPERATION
As input signals to the PCM change, the PCM
adjusts its response to output devices. For example,
the PCM must calculate a different injector pulse
width and ignition timing for idle than it does for
Wide Open Throttle (WOT). There are several differ-
ent modes of operation that determine how the PCM
responds to the various input signals.
There are two different areas of operation, OPEN
LOOP and CLOSED LOOP.
During OPEN LOOP modes the PCM receives
input signals and responds according to preset PCM
programming. Inputs from the upstream and down-
stream heated oxygen sensors are not monitored dur-
ing OPEN LOOP modes, except for heated oxygensensor diagnostics (they are checked for shorted con-
ditions at all times).
During CLOSED LOOP modes the PCM monitors
the inputs from the upstream and downstream
heated oxygen sensors. The upstream heated oxygen
sensor input tells the PCM if the calculated injector
pulse width resulted in the ideal air-fuel ratio of 14.7
to one. By monitoring the exhaust oxygen content
through the upstream heated oxygen sensor, the
PCM can fine tune injector pulse width. Fine tuning
injector pulse width allows the PCM to achieve opti-
mum fuel economy combined with low emissions.
For the PCM to enter CLOSED LOOP operation,
the following must occur:
(1) Engine coolant temperature must be over 35ÉF.
²If the coolant is over 35ÉF the PCM will wait 38
seconds.
²If the coolant is over 50ÉF the PCM will wait 15
seconds.
²If the coolant is over 167ÉF the PCM will wait 3
seconds.
(2) For other temperatures the PCM will interpo-
late the correct waiting time.
(3) O2 sensor must read either greater than 0.745
volts or less than 0.29 volt.
(4) The multi-port fuel injection systems has the
following modes of operation:
²Ignition switch ON (Zero RPM)
²Engine start-up
²Engine warm-up
²Cruise
²Idle
²Acceleration
²Deceleration
²Wide Open Throttle
²Ignition switch OFF
(5) The engine start-up (crank), engine warm-up,
deceleration with fuel shutoff and wide open throttle
modes are OPEN LOOP modes. Under most operat-
ing conditions, the acceleration, deceleration (with
A/C on), idle and cruise modes,with the engine at
operating temperatureare CLOSED LOOP modes.
IGNITION SWITCH ON (ZERO RPM) MODE
When the ignition switch activates the fuel injec-
tion system, the following actions occur:
²The PCM monitors the engine coolant tempera-
ture sensor and throttle position sensor input. The
PCM determines basic fuel injector pulse width from
this input.
²The PCM determines atmospheric air pressure
from the MAP sensor input to modify injector pulse
width.
When the key is in the ON position and the engine
is not running (zero rpm), the Auto Shutdown (ASD)
and fuel pump relays de-energize after approximately
RSFUEL INJECTION14-17
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REMOVAL
When servicing throttle body components, always
reassemble components with new O-rings and seals
where applicable. Never use lubricants on O-rings or
seals, damage may result. If assembly of component
is difficult, use water to aid assembly. Use care when
removing hoses to prevent damage to hose or hose
nipple.
(1) Disconnect negative cable from battery.
(2) Remove electrical connector from idle air con-
trol motor.
(3) Remove idle air control motor mounting screws.
(4) Remove motor from throttle body. Ensure the
O-rings is removed with the motor.
INSTALLATION
When servicing throttle body components, always
reassemble components with new O-rings and seals
where applicable. Never use lubricants on O-rings or
seals, damage may result. If assembly of component
is difficult,a light coat of engine oil may be
applied to the O-RINGS ONLY (Fig. 16)to aid
assembly. Use care when removing hoses to prevent
damage to hose or hose nipple.
(1) The new idle air control motor has a new
O-ring installed on it. For 2.4L only, if pintle mea-
sures more than 1 inch (25 mm) it must be retracted.
Use the DRB Idle Air Control Motor Open/Close Test
to retract the pintle (battery must be connected.)
(2) Carefully place idle air control motor into
throttle body.
(3) Install mounting screw(s). Tighten screws to 2
N´m (17 in. lbs.) torque.
(4) Connect electrical connector to idle air control
motor.
(5) Connect negative cable to battery.
INLET AIR TEMPERATURE
SENSOR
DESCRIPTION
The IAT Sensor is a Negative Temperature Coeffi-
cient (NTC) Sensor that provides information to the
PCM regarding the temperature of the air entering
the intake manifold (Fig. 17).
OPERATION
Inlet/Intake Air Temperature
The inlet air temperature sensor replaces the
intake air temperature sensor and the battery tem-
perature sensor. The PCM uses the information from
the inlet air temperature sensor to determine values
to use as an intake air temperature sensor and a bat-
tery temperature sensor.
The Intake Air Temperature (IAT) sensor value is
used by the PCM to determine air density.
The PCM uses this information to calculate:
²Injector pulse width
²Adjustment of ignition timing (to prevent spark
knock at high intake air temperatures)
Battery Temperature
The inlet air temperature sensor replaces the
intake air temperature sensor and the battery tem-
perature sensor. The PCM uses the information from
the inlet air temperature sensor to determine values
for the PCM to use as an intake air temperature sen-
sor and a battery temperature sensor.
The battery temperature information along with
data from monitored line voltage (B+), is used by the
PCM to vary the battery charging rate. System volt-
Fig. 16 O-RINGS
1 - O-rings
Fig. 17 3.3/3.8L IAT SENSOR
14 - 28 FUEL INJECTIONRS
IDLE AIR CONTROL MOTOR (Continued)
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