hey i thought my belt was slipping cause my car made a chirping / squeal-chatter sound. when i mash it at certain rpms. but then someone said it was pinging when i was going up hill (it "pinged" once) i'm pretty sure its just the belt still though cause it happens more sometimes with the weather, but i'm just wondering. what octane will stop pinging for sure? i've got one of them 1.5 liter sohc engines in the canadian lx civics