Checks
| Action
|
DEFINITION: A mild
to severe ping, usually worse under acceleration. The engine makes sharp metallic
knocks that change with throttle opening.
|
Preliminary
|
| • | Refer to Important Preliminary Checks Before Starting in
Symptoms
. |
|
Fuel System
|
| • | Check for items that cause the engine to run lean. |
|
Ignition System
| Check the spark plugs for proper heat range and reach.
|
Engine Cooling
System
| Check
for causes of overheating:
| • | Low engine coolant level |
| • | Restricted air flow to radiator, or restricted coolant flow through
the radiator |
|
Engine Mechanical
|
| • | Check for excessive oil in the combustion chamber-leaking valve
seals. Refer to
Oil Consumption Diagnosis
in Engine Mechanical. |
| • | Check the combustion chamber for excessive carbon buildup. Clean
using Top Engine Cleaner. |
| • | Check for incorrect basic engine parts. Inspect the following: |
|
Additional Checks
|
| • | If the scan tool readings are normal, and there are no engine
mechanical faults, fill the fuel tank with a premium gasoline that has a minimum
octane reading of 92 and re-evaluate the vehicle. |
|
