Do your cars' engines ping under light throttle? Mine pings under light throttle, 25%-35%, but it goes away under moderate throttle. It pings a bit under WOT, high rpm conditions, but no worse than it does at 25% throttle. I usually run Chevron 87 octane with FP. It pings just as bad with 76 or Shell gas, with or without FP. A compression test 2 weeks ago showed compression in all cylinders at about 170. Spec for the engine is 178 or 179 (I don't have the manual in front of me). I read in either the owner's manual or one of my maintenance manuals that light pinging under light accelaration is normal, it does it for emissions purposes or something. I don't really know what kind of pinging is light though. If somebody else's car does it, that will make me feel better, so please let me know if I'm alone in this or not. P.S. The car has 148,000 miles on it. I'd much rather figure out if this pinging is normal, or what the problem is, than run a higher grade of gas too.