Inspections
| Action
|
DEFINITION: A mild to severe ping, usually worse under acceleration. The engine makes sharp metallic knocks that change with throttle opening.
|
Preliminary
|
| • | Inspect the powertrain control module (PCM) grounds for being clean, tight, and in the proper locations. Refer to
Engine Controls Schematics
. |
| • | If the scan tool readings are normal, refer to supporting text of the Engine Controls Diagnostic Check. If there are no engine mechanical faults, fill the fuel tank with a known high quality fuel that meets the vehicles minimum octane requirements.
Road test the vehicle and re-evaluate the vehicle performance. |
|
Fuel System
|
| • | Inspect the following that may cause the engine to run lean: |
Notice: Refer to Heated Oxygen and Oxygen Sensor Notice in the Preface section. | • | Water intrusion in the HO2S connector |
| • | An exhaust leak between the HO2S and the engine--Refer to
Exhaust Leakage
. |
| • | Vacuum hoses for splits, kinks and proper connections |
|
Ignition System
| Inspect the spark plugs for being the proper heat range. Refer to
Spark Plug Inspection
.
|
Engine Cooling System
| Inspect for the following obvious overheating problems:
| • | Low engine coolant--Refer to
Loss of Coolant
for the type and amount of engine coolant to be used. |
| • | Restricted air flow to the radiator or restricted coolant flow through the radiator. |
|
Engine Mechanical
| Inspect for the following engine mechanical problems:
| • | Combustion chambers for excessive carbon buildup--Clean the combustion chamber by using top engine cleaner. Follow the instructions on the can. |
| • | Inspect the following components for incorrect basic engine parts. Refer to the appropriate procedures in Engine Mechanical: |
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