Chrysler 300M, Dodge Interpid. Manual — part 240

CONDITION

POSSIBLE CAUSES

CORRECTION

MAIN BEARING NOISE

1. Insufficient oil supply.

1. Check engine oil level.

2. Low oil pressure.

2. Check engine oil level. Inspect oil
pump relief valve and spring.

3. Thick / Thin or diluted oil.

3. Change oil to correct viscosity.

3. (a.) Change oil and filter.

(b.) Run engine to operating
temperature.

(c.) Change oil and filter again.

4. Excessive bearing clearance.

4. Measure bearings for correct
clearance. Repair as necessary.

5. Excessive end play.

5. Check thrust bearing for wear on
flanges.

6. Crankshaft journal out-of-round
or worn.

6. Replace crankshaft or grind
journals.

7. Loose flywheel or torque
converter.

7. Tighten to correct torque.

OIL PRESSURE DROP

1. Low oil level.

1. Check engine oil level.

2. Faulty oil pressure sending unit.

2. Install new sending unit.

3. Low oil pressure.

3. Check sending unit and main
bearing oil clearance.

4. Clogged oil filter.

4. Install new oil filter.

5. Worn parts in oil pump.

5. Replace worn parts or pump.

6. Thin or diluted oil.

6. Change oil to correct viscosity.

7. Oil pump relief valve stuck.

7. Remove valve and inspect, clean,
or replace.

8. Oil pump suction tube loose.

8. Remove oil pan and install new
tube or clean, if necessary.

9. Oil pump cover warped or
cracked.

9. Install new oil pump.

10. Excessive bearing clearance.

10. Measure bearings for correct
clearance.

OIL LEAKS

1. Misaligned or deteriorated
gaskets.

1. Replace gasket(s).

2. Loose fastener, broken or porous
metal part.

2. Tighten, repair or replace the
part.

3. Misaligned or deteriorated cup or
threaded plug.

3. Replace as necessary.

LH

ENGINE

9 - 7

ENGINE 3.5L (Continued)

CONDITION

POSSIBLE CAUSES

CORRECTION

OIL CONSUMPTION OR SPARK
PLUGS FOULED

1. PCV system malfunction.

1. Check system and repair as
necessary. (Refer to Appropriate
Diagnostic Manual)

2. Worn, scuffed or broken rings.

2. Hone cylinder bores. Install new
rings.

3. Carbon in oil ring slots.

3. Clean pistons and install new
rings.

4. Rings fitted too tightly in grooves.

4. Remove rings and check
grooves. If groove is not proper
width, replace piston.

5. Worn valve guide(s).

5. Replace cylinder head(s).

6. Valve stem seal(s) worn or
damaged.

6. Replace seal(s).

DIAGNOSIS AND TESTING - ENGINE DIAGNOSIS - PERFORMANCE

CONDITION

POSSIBLE CAUSE

CORRECTION

ENGINE WILL NOT START

1. Weak battery.

1. Test battery. Charge or replace
as necessary. (Refer to 8 -
ELECTRICAL/BATTERY SYSTEM/
BATTERY - DESCRIPTION)

2. Corroded or loose battery
connections.

2. Clean and tighten battery
connections. Apply a coat of light
mineral grease to terminals.

3. Faulty starter.

3. Test starting system. (Refer to 8 -
ELECTRICAL/STARTING -
DIAGNOSIS AND TESTING)

4. Faulty coil(s) or control unit.

4. Test and replace as needed.
(Refer to Appropriate Diagnostic
Information)

5. Incorrect spark plug gap.

5. Check and adjust gap as needed.

6. Contamination in fuel system.

6. Clean system and replace fuel
filter.

7. Faulty fuel pump.

7. Test fuel pump and replace as
needed. (Refer to Appropriate
Diagnostic Information)

8. Incorrect engine timing.

8. Check for a skipped timing
belt/chain or a loose camshaft
sprocket (3.2/3.5L).

9 - 8

ENGINE

LH

ENGINE 3.5L (Continued)

CONDITION

POSSIBLE CAUSE

CORRECTION

ENGINE STALLS OR IDLES
ROUGH

1. Idle speed too low.

1. Test minimum air flow. (Refer to
Appropriate Diagnostic Information)

2. Incorrect fuel mixture.

2. (Refer to Appropriate Diagnostic
Information)

3. Intake manifold leakage.

3. Inspect intake manifold gasket,
manifold, and vacuum hoses.

4. Faulty coil(s).

4. Test and replace as necessary.
(Refer to Appropriate Diagnostic
Information)

ENGINE LOSS OF POWER

1. Dirty or incorrectly gapped plugs.

1. Set gap as needed or replace
plug(s).

2. Contamination in fuel system.

2. Clean system and replace fuel
filter.

3. Faulty fuel pump.

3. Test and replace as necessary.
(Refer to Appropriate Diagnostic
Information)

4. Incorrect valve timing.

4. Correct valve timing as needed.

5. Leaking cylinder head gasket.

5. Replace cylinder head gasket.

6. Low compression.

6. Test compression of each
cylinder.

7. Burned, warped, or pitted valves.

7. Replace valves.

8. Plugged or restricted exhaust
system.

8. Check exhaust system restriction.
Replace parts, as necessary.

9. Faulty coil(s).

9. Test and replace as necessary.
(Refer to Appropriate Diagnostic
Information)

ENGINE MISSES ON
ACCELERATION

1. Dirty or incorrectly gapped spark
plugs.

1. Set gap as needed or replace
plug(s).

2. Contamination in Fuel System.

2. Clean fuel system and replace
fuel filter.

3. Burned, warped, or pitted valves.

3. Replace valves.

4. Faulty coil(s).

4. Test and replace as necessary.
(Refer to Appropriate Diagnostic
Information)

ENGINE MISSES AT HIGH SPEED

1. Dirty or incorrect spark plug gap.

1. Set gap as needed or replace
plug(s).

2. Faulty coil(s).

2. Test and replace as necessary.
(Refer to Appropriate Diagnostic
Information)

3. Dirty fuel injector(s).

Test and replace as necessary.
(Refer to Appropriate Diagnostic
Information)

4. Contamination in fuel system.

4. Clean system and replace fuel
filter.

LH

ENGINE

9 - 9

ENGINE 3.5L (Continued)

DIAGNOSIS AND TESTING - CYLINDER
COMPRESSION PRESSURE TEST

The results of a cylinder compression pressure test

can be utilized to diagnose several engine malfunc-
tions.

Ensure the battery is completely charged and the

engine starter motor is in good operating condition.
Otherwise the indicated compression pressures may
not be valid for diagnosis purposes.

(1) Check engine oil level and add oil if necessary.
(2) Drive the vehicle until engine reaches normal

operating temperature. Select a route free from traf-
fic and other forms of congestion, observe all traffic
laws, and accelerate through the gears several times
briskly.

(3) Disconnect and remove all ignition coils from

spark plugs.

(4) Remove all spark plugs from engine. As spark

plugs are being removed, check electrodes for abnor-
mal firing indicators fouled, hot, oily, etc. Record cyl-
inder number of spark plug for future reference.

(5) Be sure throttle blade is fully open during the

compression check.

(6) Insert compression gauge adaptor Special Tool

8116 or the equivalent, into the #1 spark plug hole in
cylinder head. Connect the 0–500 psi (Blue) pressure
transducer (Special Tool CH7059) with cable adap-
tors to the DRBIII

t. For Special Tool identification,

(Refer to 9 - ENGINE - SPECIAL TOOLS).

(7) Crank

engine

until

maximum

pressure

is

reached on gage. Record this pressure as #1 cylinder
pressure.

(8) Repeat the previous step for all remaining cyl-

inders.

(9) Compression should not be less than 689 kPa

(100 psi) and not vary more than 25 percent from cyl-
inder to cylinder.

(10) If one or more cylinders have abnormally low

compression pressures, repeat the compression test.

(11) If the same cylinder or cylinders repeat an

abnormally low reading on the second compression
test, it could indicate the existence of a problem in
the cylinder in question. The recommended com-
pression pressures are to be used only as a
guide to diagnosing engine problems. An engine
should not be disassembled to determine the
cause of low compression unless some malfunc-
tion is present.

DIAGNOSIS AND TESTING - CYLINDER
COMBUSTION PRESSURE LEAKAGE TEST

The combustion pressure leakage test provides an

accurate means for determining engine condition.

Combustion pressure leakage testing will detect:
• Exhaust and intake valve leaks (improper seat-

ing).

• Leaks between adjacent cylinders or into water

jacket.

• Any causes for combustion/compression pressure

loss.

WARNING: DO NOT REMOVE THE PRESSURE CAP
WITH THE SYSTEM HOT AND UNDER PRESSURE
BECAUSE SERIOUS BURNS FROM COOLANT CAN
OCCUR.

Check the coolant level and fill as required. DO

NOT install the pressure cap.

Start and operate the engine until it attains nor-

mal operating temperature, then turn the engine
OFF.

Clean spark plug recesses with compressed air.
Remove the spark plugs.
Remove the oil filler cap.
Remove the air cleaner.
Calibrate the tester according to the manufactur-

er’s instructions. The shop air source for testing
should maintain 483 kPa (70 psi) minimum, 1,379
kPa (200 psi) maximum, with 552 kPa (80 psi) rec-
ommended.

Perform the test procedures on each cylinder

according to the tester manufacturer’s instructions.
While testing, listen for pressurized air escaping
through the throttle body, tailpipe and oil filler cap
opening. Check for bubbles in the coolant.

All gauge pressure indications should be equal,

with no more than 25% leakage per cylinder.

FOR EXAMPLE: At 552 kPa (80 psi) input pres-

sure, a minimum of 414 kPa (60 psi) should be main-
tained in the cylinder.

STANDARD PROCEDURE

STANDARD PROCEDURE - FORM-IN-PLACE
GASKETS AND SEALERS

There are numerous places where form-in-place

gaskets are used on the engine. Care must be taken
when

applying

form-in-place

gaskets

to

assure

obtaining the desired results. Do not use form-in-
place gasket material unless specified. Bead size,
continuity, and location are of great importance. Too
thin a bead can result in leakage while too much can
result in spill-over which can break off and obstruct
fluid feed lines. A continuous bead of the proper
width is essential to obtain a leak-free gasket.

There are numerous types of form-in-place gasket

materials that are used in the engine area. Mopar

t

Engine RTV GEN II, Mopar

t ATF-RTV, and Mopart

Gasket Maker gasket materials, each have different
properties and can not be used in place of the other.

MOPAR

t ENGINE RTV GEN II is used to seal

components exposed to engine oil. This material is a

9 - 10

ENGINE

LH

ENGINE 3.5L (Continued)