Inspection/Test
| Action
|
DEFINITION: A mild to severe ping, usually worse under
acceleration. The engine makes sharp metallic knocks that change
with throttle opening.
|
Preliminary
|
|
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. • | Any water intrusion into the HO2S connector. |
• | An exhaust leak between the HO2S and the engine--Refer to
Exhaust Leakage
in Engine Exhaust. |
• | An inaccurate mass air flow (MAF) sensor. |
• | Vacuum hoses for splits, kinks and proper connections. |
|
Ignition System
| Inspect the spark plugs. Refer to
Spark Plug Inspection
|
Engine Cooling System
| Inspect for causes
of overheating:
• | Restricted air flow to radiator, or restricted coolant flow through
the radiator. Refer to
Engine Overheating
in Engine Cooling. |
|
Engine Mechanical
|
• | Inspect for excessive oil in the combustion chamber-leaking valve seals.
Refer to
Oil Consumption Diagnosis
in Engine
Mechanical. |
• | Inspect the combustion chamber for excessive carbon buildup. Clean using
Top Engine Cleaner. Follow instructions on can. |
• | Inspect the following for incorrect basic engine parts: |
|
Additional
|
• | Inspect the torque converter clutch (TCC) system for proper operation.
Refer to
Torque Converter Diagnosis
in Automatic Transaxle. |
• | 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. |
|