The reason why I am posting this here is it could be internal engine related


I just picked up a 98z28 and it has been tuned with ls1edit. It has heads/224 cam, stall (A4)

and it was running fine, then I take it to get smoged and ever since then the SES light cam on. But the weird part is it sounds like it pinging but louder at only half throttle? I had someone check it out and he says I am running a little rich. So I am confused on what this could be. Also how do you know when your 02's are bad?

thanks

 

Sounds like something is causing real knock. Was the tuner a respectable tuner, or did some joker just throw a bad tune in there? How long did you have it before this problem started? If your O2s were bad it would probably run like crap all the time.

 

the car was tuned by 2 good tuners. The car runs strong so I think the 02's are ok. I just talked to the previous owner of the car and he said

So what could cause detonation at half throttle?

 

I don't know. I think we would have to see the tune. Or at least a good log of what the sensors see when you get knock.