Intake Manifold Description; Diagnosis And Testing - Intake Manifold Leakage; Removal; Installation - Chrysler Vehicle User Manual

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TIMING BELT/CHAIN AND SPROCKETS (Continued)
(5) Replace the oil seal in the timing case cover
(Refer to 9 - ENGINE/ENGINE BLOCK/CRANK-
SHAFT OIL SEAL - FRONT - REMOVAL).
(6) Install the timing case cover and gasket (Refer
to 9 - ENGINE/VALVE TIMING/TIMING BELT /
CHAIN COVER(S) - INSTALLATION).
(7) With the key installed in the crankshaft key-
way, install the vibration damper (Refer to 9 -
ENGINE/ENGINE BLOCK/VIBRATION DAMPER -

INSTALLATION).

(8) Install the serpentine drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
INSTALLATION).
(9) Install the fan, hub assembly and shroud
(Refer to 7 - COOLING/ENGINE/RADIATOR FAN -
INSTALLATION).
(10) Connect negative cable to battery.
INTAKE MANIFOLD
DESCRIPTION
The intake manifold (Fig. 93) is made of cast alu-
minum and uses eleven bolts to mount to the cylin-
der head. This mounting style improves sealing and
reduces the chance of leaks.
Fig. 93 Intake Manifold 42.0L Engine
DIAGNOSIS AND TESTING - INTAKE
MANIFOLD LEAKAGE
An intake manifold air leak is characterized by
lower than normal manifold vacuum. Also, one or
more cylinders may not be functioning.
WARNING: USE EXTREME CAUTION WHEN THE
ENGINE IS OPERATING. DO NOT STAND IN A
DIRECT LINE WITH THE FAN. DO NOT PUT YOUR
HANDS NEAR THE PULLEYS, BELTS OR THE FAN.
DO NOT WEAR LOOSE CLOTHING.
(1) Start the engine.
(2) Spray a small stream of water at the suspected
leak area.
(3) If a change in RPM is observed the area of the
suspected leak has been found.
(4) Repair as required.

REMOVAL

NOTE: THE ENGINE INTAKE AND EXHAUST MANI-
FOLD MUST BE REMOVED
TOGETHER. THE MANIFOLDS USE A COMMON
GASKET AT THE CYLINDER HEAD.
(1) Disconnect the battery negative cable.
(2) Remove air cleaner inlet hose from the resona-
tor assembly.
(3) Remove the air cleaner assembly.
(4) Remove the throttle cable, vehicle speed control
cable (if equipped) and the transmission line pres-
sure cable (Refer to 21 - TRANSMISSION/TRANS-
AXLE/AUTOMATIC
CABLE - REMOVAL).
(5) Disconnect the following electrical connections
and secure their harness out of the way:
• Throttle Position Sensor
• Idle Air Control Motor
• Coolant Temperature Sensor (at thermostat
housing)
• Intake Air Temperature Sensor
• Oxygen Sensor
• Crank Position Sensor
• Six (6) Fuel Injector Connectors
• Manifold Absolute Pressure (MAP) Sensor.
(6) Disconnect HVAC, and Brake Booster vacuum
supply hoses at the intake manifold.
(7) Perform the fuel pressure release procedure.
(Refer to 14 - FUEL SYSTEM/FUEL DELIVERY -
STANDARD PROCEDURE).
(8) Disconnect and remove the fuel system supply
line from the fuel rail assembly.
(9) Remove the accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL).
(10) Remove the power steering pump from the
intake manifold and set aside.
(11) Raise the vehicle.
(12) Disconnect the exhaust pipes from the engine
exhaust manifolds.
(13) Lower the vehicle.
(14) Remove the intake manifold and exhaust
manifold bolts and manifolds (Fig. 94).
INSTALLATION
If the manifold is being replaced, ensure all the fit-
ting, etc. are transferred to the replacement manifold.
(1) Install a new engine exhaust/intake manifold gas-
ket over the alignment dowels on the cylinder head.
ENGINE 4.0L
AND INSTALLED
- AW4/THROTTLE
9 - 127
VALVE