"dwana" <dwanak@earthlink.net> wrote in message
news:K6msf.3490$R84.3288@newsread2.news.pas.earthl ink.net...
> Hello:
>
> I've recently noticed some pinging in my car at low RPM (less than 2000).
> I don't hear anything at RPM above 3000. I checked all the plugs, plug
> wires, timing and everything looks OK. I recently changed to BOSCH plugs
> instead of NGK.
>
> Anyone have any ideas on likely causes of pinging? Thanks.
>
> PK
>
Sounds like the new plugs are the wrong heat range for your engine. Plugs in
higher heat ranges reach farther into the combustion chamber and can get hot
enough to pre-ignite the fuel.

Mike