01MaroZ28

I read something a couple days ago here about the HPP III not really helping in performance so I decided to put my car back to "stock". So after I finished programming it back to stock I took a spin on the freeway and floored it and it didn't feel as powerful and even more worrying it made a crackling noise as it was climbing into the high rpms. So I took it back home and reprogrammed it to my liking and now it really flies but still makes that crackling noise and I don't know what it is. It wasn't doing it before so now I think I f***ed up my car. Does anyone know what this is or what it could be? Feel free to move this to another forum if necessary. Any help is appreciated.

rocketrider93

could it possibly be something to do with your timing curve is it like a pinging. not knowing exactly what the noise is its hard to tell. are you running 92 unleaded or are you running the cheap gas? you could be pinging which is bad gas or timing. you may need to adjust the curve or something. usually pinging sounds like a crackle i guess and happens under accelleration and high revs.

01MaroZ28

I'm always runnin' the good ****, which is 91 octane so it can't be that. And it does happen during high revs like WOT situations so maybe it is the timing. There's no way it could be the cats? Or anything else?

rocketrider93

well the problem is if it was your cats it would almost have to be because the catalyst was breaking up but you would hear it rattle when you hit a bump or something or even at an itle possibly. i am not an ase mechanic kind of a shade tree one but if it is happening at acceleration only that is hard to say. if you r cat became plugged up it might make some sound but since you have power i am sure your cats aren't plugged. since your fuel is good i can only assume you should have the timing checked. since all that is controlled by the computer and that is what you were messing with with the tuner i would say something got tweeked when you were in there. of course there are always other things it could be. have you checked for any exhaust leaks that could be blowing out when there is more pressure in the system. does it do it when you rev the car in neutral or just under load. usually timing pings happen under load. put it in neutral with the brake on and rev it from under the hood and see if you hear anything. i would just say check the timing. i may be wrong but noone else is chiming in so i don't know. timing may be fine at itle but your curve may be off or you may have a bad sensor. your curve may be retarted at higher rpm. try advancing it a bit. i am sure your cats are fine along with the car. but if you keep pinging her around she may not like you very much. hope this helps.