Originally Posted By: MaximaGuy
The ping is from the coils, they are on their way out.
As Ducked already noted, pinging has nothing to do with the coils, maybe you are thinking of a misfire?
Pinging, or ignition knock, is often the result of, but not limited to, too much ignition timing relative to the knock resistance of the fuel in use. This is why knock sensors are used to keep an eye on it and retard the timing if pinging occurs.
Some OEM tunes, for the pursuit of fuel economy will allow "mild" (you can hear it...) ignition knock and claim it is OK. Ford is one I can think of, as I believe it was common with the 3V Modular.
Note that knock can also be mitigated by a richer mixture but generally, IIRC, ignition timing retard is commonly used the most as the control mechanism.
There are other factors that can contribute to an engine's propensity to knock, but that's not really relevant to the thread when were are talking about a stock vehicle/engine here.
Nick:
See if there's a TSB that deals with this, which may include an updated PCM map with revised timing tables. If not, and the OEM says it is "normal", then your only real option to mitigate it is an aftermarket tune or running higher octane fuel unfortunately