It doesn't ping much now and it's not too noticable unless you really listen for it. I did the timing belt about 6k ago. (And yes, it is done right) I have my MAF sensor unplugged b/c it runs real bad when it's plugged in. When the MAF is hooked up it pings alot. I was thinking it is the knock sensor but not sure. Is there any way to test it? Also I do have a bad headgasket (can't afford that yet) Could it be the coolant- oil mixture doing this? It still has all kinds of power and no smoke yet. I only drive it about ten miles a day. I can hear it while it is under load only. Any ideas would help and thanks.