Dodge 2000 DURANGO Service Manual page 655

DN
DIAGNOSIS AND TESTING (Continued)
CONDITION
OIL LEAKS 1. Misaligned or
deteriorated gaskets
2. Loose fastener,
broken or porous metal
part
3. Front or rear
crankshaft oil seal
leaking
4. Leaking oil gallery
plug or cup plug
5. Leaking intake
manifold cross-over
gaskets
EXCESSIVE OIL 1. PCV System
CONSUMPTION malfunction
OR SPARK
PLUGS OIL
FOULED
2. Intake manifold
plenum pan gasket
failure
3. Defective valve
stem seal(s)
4. Worn or broken
piston rings
5. Scuffed pistons/
cylinder walls
6. Carbon in oil control
ring groove
7. Worn valve guides
8. Piston rings fitted
too tightly in grooves
INTAKE MANIFOLD LEAKAGE DIAGNOSIS
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.
POSSIBLE CAUSES
1. Replace gasket
2. Tighten, repair or replace the part
3. Replace seal
4. Remove and reseal threaded plug. Replace cup style plug
5. Replace gaskets
1. Refer to group 25, Emission Control System for correct
operation
2. Replace plenum
pan gasket
3. Replace seals
4. Hone cylinder bores. Install new rings
5. Hone cylinder bores and replace pistons as required
6. Remove rings and de-carbon piston
6. Repair as
necessary
8. Remove rings and
check ring end gap
and side clearance.
Replace if necessary
(1) Start the engine.
(2) Spray a small stream of water at the suspected
leak area.
(3) If a change in RPMs, the area of the suspected
leak has been found.
(4) Repair as required.
CYLINDER COMPRESSION PRESSURE TEST
The results of a cylinder compression pressure test
can be utilized to diagnose several engine malfunc-
tions.
5.9L ENGINE
CORRECTION
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