Checks
| Action
|
DEFINITION: A mild
to severe ping which is usually worse upon acceleration. The engine makes
sharp metallic knocks which change with the throttle opening.
|
Preliminary Checks
|
| • | Make sure that the vehicle has an actual problem. |
|
Cooling
System Checks
|
| • | Check for a low engine coolant level. |
| • | Check for a loose water pump belt. |
| • | Check for restricted air flow through the radiator, or restricted
coolant flow. |
| • | Check for a malfunctioning or incorrect thermostat. |
| • | Check for a correct coolant solution. The solution should be a
50/50 mix of anti-freeze and water. |
|
Sensor
Check
| Check
the engine coolant temperature (ECT) sensor. Use the scan tool in order to
compare the engine coolant temperature with the ambient air temperature
on a cold engine. If the coolant temperature reading is more than 5°
more or less than the ambient air temperature on a cold engine, check
for a high resistance in the coolant sensor circuit or the sensor itself.
|
Fuel System Checks
|
|
Engine
Mechanical Checks
|
| • | Check for incorrect basic engine parts such as the cam, the heads,
the pistons, etc. |
| • | Check for any excessive oil entering the combustion chamber. |
|
Additional
Checks
| Check
the Service Bulletins for control module software updates.
|
