Condition
|
Action
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Abnormalities (severe cracking, bumps or missing areas) in the
accessory drive belt. Also worn, damaged, or misaligned accessory
drive components or excessive pulley runout.
|
Abnormalities in the accessory drive belt and/or components may
cause engine RPM variations, noises similar to a faulty lower
engine and also lead to a misfire condition. A misfire code may be
present without an actual misfire condition.
|
1. |
Inspect the accessory drive components. |
|
2. |
Repair or replace all damaged components. |
|
Loose and/or damaged crankshaft pulley
|
A misfire code may be present without an actual misfire
condition.
|
1. |
Inspect crankshaft pulley and pulley bolt |
|
2. |
Repair or replace all damaged components. |
|
Loose and/or damaged flywheel
|
A misfire code may be present without an actual misfire
condition.
|
1. |
Inspect flywheel and flywheel attaching
bolts. |
|
2. |
Repair or replace all damaged components. |
|
Restricted exhaust system
|
A severe restriction in the exhaust flow can cause significant
loss of engine performance and may set a misfire code. Possible
causes of restrictions include collapsed or dented pipes, plugged
mufflers and/or catalytic converters. Repair or replace all damaged
components.
|
Air in fuel system
|
|
1. |
Inspect fuel filter, fuel system for leaks and/or
restrictions. |
|
2. |
Repair or replace all damaged components. |
|
Bent and/or worn valve bridge and finger-follower
|
|
1. |
Inspect valve bridge and valve
finger-follower. |
|
2. |
Repair or replace all damaged components. |
|
Sticking valve
|
Carbon on the valve stem or valve seat may cause the valve to
stick.
|
1. |
Inspect valves and valve guides. |
|
2. |
Repair or replace all damaged components. |
|
Damaged or misaligned timing gears
|
|
2. |
Replace all damaged components. |
|
Worn or faulty camshaft lobes
|
|
1. |
Inspect camshaft lobes. |
|
2. |
Repair or replace all damaged components. |
|
Excessive piston-to-cylinder bore clearance
|
|
1. |
Perform compression tests. |
|
2. |
Inspect the piston, piston rings and cylinder
bore. |
|
3. |
Repair or replace all damaged components. |
|
Faulty cylinder head gaskets and/or cracking or other damage to
the cylinder heads and engine block cooling system passages.
(Coolant consumption may or may not cause the engine to
overheat.)
|
|
1. |
Perform compression tests. |
|
2. |
Inspect the piston, piston rings and cylinder
bore. |
|
3. |
Repair or replace all damaged components. |
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