Detonation - Pings, Spark Knock

A mild to severe ping, usually worse under load or acceleration. Sounds like something is rattling or knocking in the engine.

POSSIBLE CAUSE ACTION


Ignition timing advanced ^ Check Distributor Assembly installation.


Spark timing not retarding ^ Check Spark Controls,


Lean Air-Fuel mixture ^ Check Air-Fuel ratio, O2 sensor, perform injector balance test, inspect regulator operation (check vacuum line and return hose), check fuel pressure


EGR malfunction ^ Check EGR system, Exhaust Gas Recirculation


Poor or contaminated fuel ^ Recommend higher grade fuel