Yippers®

'solution' is to decarbon the heads. I'm not saying it IS a carbon build up issue but it is likely. I had my car MotorVac'd at ~50k miles and although I had/have no pinging, (Stage III kit) it made a world of difference in how smooth the car runs. I am about to spring for the ~120$ to have it run again @ ~80k. Pinging is typically caused by the mixture pre-igniting from too low an octane fuel, too lean a mixture or excessive heat causing the fuel to ignite either before the spark is requested by the ECU or with too fast a flame front. Carbon deposits can easily provide that ignition source.

ColoradoMark

thanks for your thoughts guys!

JWG

If plugs look good, I would focus on fuel system and cleaning combustion chamber and valves.

First try running a can of BG 44k once or twice. Do not waste your time using the cheap off-the shelf stuff from Pep Boys or other places once you notice a problem. Invest in the good stuff from a reputable garage.

Second, get a machine cleaning on a BG, Bilstein, or similar fuel system cleaning machine that plugs into your fuel rail in place of the fuel line and runs the car on a combustible fuel cleaner.

Third, send your injectors to a lab for ultra-sonic cleaning and balancing. At 60,000-75,000, miles your engine become due; by 90,000-100,000 miles, your engine becomes past due for a good cleaning.

I have 150,000+ miles on my 12v and have had a mighty battle with carbon deposits and clogged injectors due to my ignorance and belief in gas company additive propaganda. Never again, I run mild cleaners regularly and will do another major cleaning between the 160,000 to 175,000 mile interval.