this noise is a paine in the ***. i have a 98 formula trans am. When u start the car the loud noise comes on. After like 2 minutes it will shut off. Does anybody know what this noise could be?

 

I have it too. Mine is a squealing sound.

 

a.i.r pumps

 

Yeah, what he says. It's a smog thing, when the car is not at normal operating temp the smog pump(a.i.r) starts up, I think it adds air into the exhaust which makes the gasses easier to combust in the cats...Or something like that!

Once the engine warms up(or the cats!), the smog pump shuts off...

 

ugh no you don't. You either have a Formula or a Trans Am.

 

do you kno how to get rid of that noise?
thanx

 

I had the same exact whining noise upon upon startup also, it turned out to be the A.I.R. checkvalve.