I have had my car for almost a year, and I remember even when buying it, there was a weird sound (kinda like "whir whir whir whir whir") that even travels through the exhaust to amplify the sound when I start the car and drive it for the first 10 seconds or so. It sounds like the alternator is charging and then releases belt tension or something, because the noise stops and the car is fine afterwards (when the noise stops, the whirring stops and it sounds like a drill turning off). I would like to believe it is related to the alternator, because it only does it on startup, and sometimes does it for longer periods than others. I have not noticed any correlation to ambient temperature, how long it is ran, etc. Does anybody know what this noise is, even the previous owner did not know what it was. I can tell you that the car does run fine with no engine codes/temperature problems/charging problems. Thanks.

 

I believe thats just the AIR pump for emissions.

 

Yep, you can check to be sure by pulling the AIR PUMP fuse.

 

AIR pump.

 

Thats strange, it kind of makes my car sound like a piece of S*&T upon start up. I suppose there is no way to stop this sound (other than pulling the fuse, which I opt not to do for a long period of time because this is probably not too good for the engine and components). Well, at least I know that this is somewhat normal. Thanks.

 

I don't think anybody said anything about taking the fuse out and keeping it out. Just pull it out to check whether the noise appears with it not there and once you have verified, then put it back in.

 

Sorry, should have elaborated. I meant pull the fuse to make sure it's the pump that's making the noise. Also, pulling it will throw code P0412, but turn off the SES after a few cold starts by itself once it's replaced. My pump is fairly quiet, all I can hear is the air whistling through the lid hose filter - yours might be on the way out.

 

Yea one thing about that is I have a 99 LS1. I noticed you have an 01'. My lid doesnt have the provisions for the AIR system like the 01-02s (and maybe 2000s), it just goes through the MAF and into the intake. I wonder what I can do to make this thing quieter, it sounds kinda weird.