Dodge Dakota (R1). Manual — part 507

CONDITION

POSSIBLE CAUSES

CORRECTION

3. Worn or incorrectly gapped spark
plugs

3. Replace or clean and re-gap
spark plugs (Refer to 8 -
ELECTRICAL/IGNITION CONTROL/
SPARK PLUG - CLEANING)

4. Worn or burned distributor rotor

4. Install new distributor rotor

5. Spark plug cables defective or
crossed

5. Check for correct firing order or
replace spark plug cables. (Refer to
8 - ELECTRICAL/IGNITION
CONTROL/SPARK PLUG CABLE -
DIAGNOSIS AND TESTING)

6. Faulty coil

6. Test and replace, if necessary
(Refer to 8 - ELECTRICAL/
IGNITION CONTROL/IGNITION
COIL - REMOVAL)

7. Intake manifold vacuum leak

7. Inspect intake manifold gasket
and vacuum hoses (Refer to 9 -
ENGINE/MANIFOLDS/INTAKE
MANIFOLD - DIAGNOSIS AND
TESTING).

ENGINE MISSES ON
ACCELERATION

1. Worn or incorrectly gapped spark
plugs

1. Replace spark plugs or clean and
set gap. (Refer to 8 - ELECTRICAL/
IGNITION CONTROL/SPARK PLUG
- CLEANING)

2. Spark plug cables defective or
crossed

2. Replace or rewire secondary
ignition cables. (Refer to 8 -
ELECTRICAL/IGNITION CONTROL/
SPARK PLUG CABLE - REMOVAL)

3. Dirt in fuel system

3. Clean fuel system

4. Burned, warped or pitted valves

4. Install new valves

5. Faulty coil

5. Test and replace as necessary
(Refer to 8 - ELECTRICAL/
IGNITION CONTROL/IGNITION
COIL - REMOVAL)

DIAGNOSIS AND TESTING— ENGINE
DIAGNOSIS - MECHANICAL

ENGINE MECHANICAL DIAGNOSIS CHART

CONDITION

POSSIBLE CAUSES

CORRECTION

NOISY VALVES/LIFTERS

1. High or low oil level in crankcase

1. Check for correct oil level. Adjust
oil level by draining or adding as
needed

2. Thin or diluted oil

2. Change oil. (Refer to 9 -
ENGINE/LUBRICATION/OIL -
STANDARD PROCEDURE)

9 - 216

ENGINE 5.9L

AN

ENGINE 5.9L (Continued)

CONDITION

POSSIBLE CAUSES

CORRECTION

3. Low oil pressure

3. Check engine oil level. If ok,
Perform oil pressure test. (Refer to
9 - ENGINE/LUBRICATION -
DIAGNOSIS AND TESTING) for
engine oil pressure test/
specifications

4. Dirt in tappets/lash adjusters

4. Clean/replace hydraulic
tappets/lash adjusters

5. Bent push rod(s)

5. Install new push rods

6. Worn rocker arms

6. Inspect oil supply to rocker arms
and replace worn arms as needed

7. Worn tappets/lash adjusters

7. Install new hydraulic tappets/lash
adjusters

8. Worn valve guides

8. Inspect all valve guides and
replace as necessary

9. Excessive runout of valve seats
or valve faces

9. Grind valves and seats

CONNECTING ROD NOISE

1. Insufficient oil supply

1. Check engine oil level.

2. Low oil pressure

2. Check engine oil level. If ok,
Perform oil pressure test. (Refer to
9 - ENGINE/LUBRICATION -
DIAGNOSIS AND TESTING) engine
oil pressure test/specifications

3. Thin or diluted oil

3. Change oil to correct viscosity.
(Refer to 9 - ENGINE/
LUBRICATION/OIL - STANDARD
PROCEDURE) for correct
procedure/engine oil specifications

4. Excessive connecting rod
bearing clearance

Measure bearings for correct
clearance with plasti-gage. Repair
as necessary

5. Connecting rod journal out of
round

5. Replace crankshaft or grind
journals

6. Misaligned connecting rods

6. Replace bent connecting rods

MAIN BEARING NOISE

1. Insufficient oil supply

1. Check engine oil level.

2. Low oil pressure

2. Check engine oil level. If ok,
Perform oil pressure test. (Refer to
9 - ENGINE/LUBRICATION -
DIAGNOSIS AND TESTING)

3. Thin or diluted oil

3. Change oil to correct viscosity.

4. Excessive main bearing
clearance

4. Measure bearings for correct
clearance. Repair as necessary

5. Excessive end play

5. Check crankshaft thrust bearing
for excessive wear on flanges

6. Crankshaft main journal out of
round or worn

6. Grind journals or replace
crankshaft

AN

ENGINE 5.9L

9 - 217

ENGINE 5.9L (Continued)

CONDITION

POSSIBLE CAUSES

CORRECTION

7. Loose flywheel or torque
converter

7. Inspect crankshaft, flexplate/
flywheel and bolts for damage.
Tighten to correct torque

LOW OIL PRESSURE

1. Low oil level

1. Check oil level and fill if
necessary

2. Faulty oil pressure sending unit

2. Install new sending unit

3. Clogged oil filter

3. Install new oil filter

4. Worn oil pump

4. Replace oil pump assembly.

5. Thin or diluted oil

5. Change oil to correct viscosity.

6. Excessive bearing clearance

6. Measure bearings for correct
clearance

7. Oil pump relief valve stuck

7. Remove valve to inspect, clean
and reinstall

8. Oil pump suction tube loose,
broken, bent or clogged

8. Inspect suction tube and clean or
replace if necessary

9. Oil pump cover warped or
cracked

9. Install new oil pump

OIL LEAKS

1. Misaligned or deteriorated
gaskets

1. Replace gasket

2. Loose fastener, broken or porous
metal part

2. Tighten, repair or replace the part

3. Front or rear crankshaft oil seal
leaking

3. Replace seal

4. Leaking oil gallery plug or cup
plug

4. Remove and reseal threaded
plug. Replace cup style plug

EXCESSIVE OIL CONSUMPTION
OR SPARK PLUGS OIL FOULED

1. CCV System malfunction

1. (Refer to 25 - EMISSIONS
CONTROL/EVAPORATIVE
EMISSIONS - DESCRIPTION) for
correct operation

2. Defective valve stem seal(s)

2. Repair or replace seal(s)

3. Worn or broken piston rings

3. Hone cylinder bores. Install new
rings

4. Scuffed pistons/cylinder walls

4. Hone cylinder bores and replace
pistons as required

5. Carbon in oil control ring groove

5. Remove rings and de-carbon
piston

6. Worn valve guides

6. Inspect/replace valve guides as
necessary

7. Piston rings fitted too tightly in
grooves

7. Remove rings and check ring end
gap and side clearance. Replace if
necessary

9 - 218

ENGINE 5.9L

AN

ENGINE 5.9L (Continued)

DIAGNOSIS AND TESTING—ENGINE
DIAGNOSIS - LUBRICATION

CONDITION

POSSIBLE CAUSES

CORRECTION

OIL LEAKS

1. Gaskets and O-Rings.

1.

(a) Misaligned or damaged.

(a) Replace as necessary.

(b) Loose fasteners, broken or
porous metal parts.

(b) Tighten fasteners, Repair or
replace metal parts.

2. Crankshaft rear seal

2. Replace as necessary.

3. Crankshaft seal flange.
Scratched, nicked or grooved.

3. Polish or replace crankshaft.

4. Oil pan flange cracked.

4. Replace oil pan.

5. Timing chain cover seal,
damaged or misaligned.

5. Replace seal.

6. Scratched or damaged vibration
damper hub.

6. Polish or replace damper.

OIL PRESSURE DROP

1. Low oil level.

1. Check and correct oil level.

2. Faulty oil pressure sending unit.

2. Replace sending unit.

3. Low oil pressure.

3. Check pump and bearing
clearance.

4. Clogged oil filter.

4. Replace oil filter.

5. Worn oil pump.

5. Replace as necessary.

6. Thin or diluted oil.

6. Change oil and filter.

7. Excessive bearing clearance.

7. Replace as necessary.

8. Oil pump relief valve stuck.

8. Clean or replace relief valve.

9. Oil pump suction tube loose or
damaged.

9. Replace as necessary.

OIL PUMPING AT RINGS; SPARK

PLUGS FOULING

1. Worn or damaged rings.

1. Hone cylinder bores and replace
rings.

2. Carbon in oil ring slots.

2. Replace rings.

3. Incorrect ring size installed.

3. Replace rings.

4. Worn valve guides.

4. Ream guides and replace valves.

5. Leaking intake gasket.

5. Replace intake gaskets.

6. Leaking valve guide seals.

6. Replace valve guide seals.

DIAGNOSIS AND TESTING—CYLINDER
COMPRESSION PRESSURE

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) Clean the spark plug recesses with compressed

air.

(2) Remove the spark plugs (Refer to 8 - ELEC-

TRICAL/IGNITION

CONTROL/SPARK

PLUG

-

REMOVAL).

(3) Secure the throttle in the wide-open position.
(4) Disconnect the ignition coil.
(5) Insert a compression pressure gauge and rotate

the engine with the engine starter motor for three
revolutions.

AN

ENGINE 5.9L

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ENGINE 5.9L (Continued)