Detonation, Spark Knock

DEFINITION: A mild to severe ping, usually worse under acceleration. It sounds like popcorn popping.

Check for overheating problems:
^ Low coolant
^ Loose drive belt
^ Restricted air flow through radiator, or restricted air flow through condensor.
^ Proper cooling fan operation.
^ Proper thermostat operation.
^ Correct coolant/water concentration.

Check:
^ Knock sensor circuit system for no spark retard, during the knock condition.
^ TCC operation. TCC applying too soon can cause the engine to spark knock.
^ Proper fuel pressure.

Remove carbon with top engine cleaner:
^ Cheek to see if engine is running lean (monitor long term fuel trim for significant positive values). Refer to P0171. P0171
^ Check for excessive oil in combustion chamber.
^ Cheek for poor fuel quality, proper octane rating.
^ Check for correct spark plugs.

Fuel with higher octane ratings can eliminate problem.