Hey all... ok so just the other day my 09 ss started make a funny noise and over boosting when I lay down the gas. On top of hearing the turbo spooling there's a high pitch squeling. It almost sounds like a dentist dril. The boost climbs to 15 like it always has, but now at about 4500 rpm the gauge rises then right bfore I I shift I look and its at 18/19 pounds. Trust me I'm not complaining about the extra boost its just the god awful noise. Any input???

 

i forget what mine was when that happened..... but i got it fixed right away i suggest you not wait

 

It's a pure boost leak, check your hoses carefully and tighten them. Overboost must be caused by the "learn down" feature trying to compensate for the amount of air the system looses.

 

Yup you have a leak somewhere

 

I've seen 20psi in 4th gear on a stock car.

 

sounds like turbo surging....which is not good...but thats weird on a stock turbo...i mean you would have to do something to create the surge...someone correct me if im wrong

 

The highest boost rating I have seen so far was when I was at the track on Sunday, it was 85 degrees outside & I was pulling in 123 degree heat (inlet air temp) and it was 18.8 psi WOT at the top end of third, and even in fourth

 

alright thanks guys i just threw the stock intake back in and took it to the dealer anyway because i wanted to take it there for the first oil change anyway.. i will repost and let everyone know what exactly was wrong. i told them to put new charge piping in because the cheap little bracket was broken and it was sitting right on top of the engine.

 

So I just got my car back from the dealer. "Everything is fixed" ok I checked the back roters ?nice and smooth check the charge piping?brand new. Drive it out of there, floor it to see if they fixed the noise and its still doing it. Wtf???? I cwent bsack and they said oh we didn't hear a noise.. so then I took the supervisor for a ride and he tells me its normal!!! Um no sorry its not supposed to sound like a sc on top of the tc. So what should I check? I have no clue where to even start... help meee!!! Plz!!!! I have a dejon short ram and a muffler delete and that's all....

 

Exhaust leak?

 

In reality it is normal, you ecu wants to make "260hp/260tq" and if it has to raise the boost to make it-it will. It adjust everything from a/f, boost etc to get to the desired mark. When its cooler outside and the air is more dense you actually make less boost or at least that's how it should work...

 

I'm not worried about the boost being high though its the screaming noise I'm worried about.

Tear

 

you dont like when ur bitches scream?

 

do you know what a turbo sounds like? not trying to be funny, i'm really asking. Is it possible that it's just the way it sounds, but it's a new car to you so you think it sounds weird?

 

Yes I know what a turbo sounds like... this squeling over powers the spooling.. its different

 

Have you checked your trunk? You may have a midget or a leprechaun in the back, and whenever you WOT it gets all giddy, and starts squealing. Damn those little *******...

 

lmao

 

Is there a chev dealer that knows anything about a cobalt? I went to my dealer to ask when the stage kit was out for the SS/TC....Parts guy looks at me and says "Whats a stage kit?"

 

mine did the same thing when i installed my hahn charge pipeing, sounded like a supercharged. LOL i know whats wrong. Tighten the tbolt on ur charge pipe that connects to the turbo. if u have the hahn charge pipes, the tbolt they give u for that connection is a little to big, use the stock one and ur problem will be solved.