JunebugSS

hey people, i am new to this post thing so please bear with me, i just got myself the 2006 cobalt ss 3 months ago, i just took it to the shop because it is over boosting at low rpm's, when u get to 4grand, it is completely maxing out the boost guage and it starts to miss and it sounds like a knocking noise, but i could be wrong about the knocking noise, but i was just wondering if anyone out there has any ideas on what it could be. any help is greatly appreciated.

J.D.

Sounds like detonation to me. *shrug*. What octane gas are you running?

Drewfu$

Any check engine lights? Thats a good place to start.

How many miles are on it? Did it just start doing this? Or has it always been doing it?

Dman

Yeah if youve got less than 90octane in there then beating on it is a bad idea

when the dealership mistakenly put 89 in mine, i didnt beat on it till i got to fill it up...

let us know what the culprate ends up being...

welcome to the site?

JunebugSS

it was actually the catalytic converter, it had plaugged it up, i am burnin supreme in it with is the highest octane i can get for it on pei

JunebugSS

there are just over 7 on it, no check engine lights came on