I have a 2004 GTP Comp G with about 50k. The car is completely stock except it has a Spectre cone filter and a 180* thermostat. I have always used premium gas and fuel injection cleaner every 3-4k miles.
I have recently noticed some pinging coming from the engine when I am slowly accelerating say up a hill (45-50 MPH). I can really hear it from 1200-1800 RPM's while in 4th gear. Once the car downshifts into 3rd gear it is almost non-existent. Under WOT I can't hear any pinging at all (not sure if that is because of the supercharger whine).
I am not sure what is going on or what I can do to fix it. It looks like the car has had the plugs/wires changed by the previous owner but I may change them again to be safe. Any ideas would be much appreciated, thanks!
