I have heard the term engine ping before. What exactly is it and what can cause it? Is it the same as engine knock?
When I start my engine, sometimes I can hear what sounds like a clicking or ticking noise when my windows are closed and radio off. Is this an engine ping?

 

Engine ping always occurs when the engine is under load (going up a hill or accelerating are favorites, just before the transmission downshifts). It is caused by: Ignition timing too early, octane of gasoline below required, compression ratio of the engine too high for gasoline octane rating being used. It is best described as a "clink, clink, clinkity-clink" sound
as the engine is being accelerated or going up a hill. Also has been decsribed as a "herd of ping-pong ***** bouncing under the hood".
The TPI setup uses a "knock sensor" to detect when this happens and the ECM then retards the ignition timing to make it stop.
A ticking or clicking sound at idle are usually related to worn valve train parts or an engine with excessive wear.
Engine knock is a much louder, lower pitched sound. Imagine a baseball in a metal bucket and you are shaking the bucket violently from side to side. THIS is a good example.

 

that does sound like detonation funny it is at idle like that... see the exhaust glowing...