i have a 2006 cobalt. my car has been making a whistling sound when i am in drive but only when i am in motion. when i apply the breaks the noise goes away.... when i put it in reverse my car makes a almost quiet vacume noise but not when i apply the breaks... is this a break problem or do i need to take it in to get checked ? please help me out

my check engine light has also been on for the last 7 months. i havent taken it in professionally yet becasue when i went to autozone they check engine codes for free but the guy just told me that there was no code with it and that it shouldn't be anything so i haven't taken it in yet only cause it will cost me up to $100 just to see whats wrong with it...

thank you to whom ever can help me out

~wisconsin girl~

 

I can't think of a "whistling sound" that behaves like that. If the noise is more like a metal-on-metal squeal, it may be a brake wear indicator touching a rotor which is a warning that the front brakes need servicing. That noise often goes away or turns into a scraping noise when the brakes are applied. As far as the malfunction indicator goes, it's not too late to get it checked out. You don't want to wait until it strands you somewhere.