Intake Manifold Description; Operation; Diagnosis And Testing - Intake Manifold Leaks; Intake Manifold - Upper - Dodge Intrepid Service Manual

9 - 72 ENGINE 2.7L
INTAKE MANIFOLD
DESCRIPTION
The two piece intake manifold is made of a com-
posite material. The intake manifold features a com-
pact, low rumble design that maximizes engine
performance while minimizing induction noise.

OPERATION

The intake air plenum chambers absorb air pulsa-
tions created during each cylinder's intake stroke.
DIAGNOSIS AND TESTING - INTAKE
MANIFOLD LEAKS
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 (Spray Bottle) at
the suspected leak area.
(3) If engine RPM'S change, the area of the sus-
pected leak has been found.
(4) Repair as required.

INTAKE MANIFOLD - UPPER

STANDARD PROCEDURE - INTAKE MANIFOLD
VACUUM PORT REPAIR
The composite intake manifold vacuum ports can
be repaired. Although, if the manifold plenum cham-
ber is damaged or cracked, the manifold must be
replaced.
To repair a broken or damaged vacuum nipple
(port) on the composite intake manifold, perform the
following procedure:
PARTS REQUIRED
Brass Nipple – 3/8 O.D.
x 1/4 pipe thread (Speed
Control Port)
Brass Nibble – 1/2 O.D.
x 1/4 pipe thread (Brake
Booster Port)
NOTE: While performing this procedure, avoid get-
ting the manifold material residue into the plenum
chamber.
TOOLS REQUIRED
Pipe Tap – 1/4 - 18 NPT
Drill Bit – 7/16
File/Sand Paper
(1) File or sand the remaining port back until a
flat surface is obtained (plane normal to nipple (port)
axis).
(2) Drill out the nipple (port) base using a 7/16"
drill bit (Fig. 104).
(3) Using a 1/4"–18 NPT pipe tap, cut internal
threads (Fig. 104). Use caution to start tap in a axis
same as original nipple.
(4) Apply Mopar Thread Sealant to threads of
repair nipple(s).
(5) Install repair nipple(s). Do not over torque
repair nipple(s).
Fig. 104 MANIFOLD PORT (NIPPLE) REPAIR
1 - 1/4" — 18NPT PIPE TAP
2 - NIPPLE (PORT)

REMOVAL - UPPER

(1) Disconnect negative cable from battery remote
jumper terminal.
(2) Disconnect Inlet Air Temperature (IAT) Sensor
connector. Remove air inlet resonator and inlet tube.
(3) Remove throttle cable and speed control cable
from throttle arm and bracket (Refer to 14 - FUEL
SYSTEM/FUEL INJECTION/THROTTLE CONTROL
CABLE - REMOVAL).
(4) Remove throttle cable bracket.
(5) Disconnect electrical connectors from the fol-
lowing components:
• Manifold Absolute Pressure (MAP) Sensor
• Throttle Position Sensor (TPS) Sensor
• Idle Air Control (IAC) Motor
(6) Disconnect Vapor Purge hose, Brake Booster
hose, Speed Control Servo, Positive Crankcase Venti-
lation (PCV) hose (Fig. 105).
LH