milburnr

I have been hearing a whistle or really high-pitched while at idle when the car is first started. A friend said, "hey, you've got a vacuum leak... rev it... see it stops... now it's back... is that a turbo? are you sure you don't have a turbocharger?" And then... it stopped, with a faint rushing sound like some circuit or something kicked on.

I have LTs with the EGR and AIR connections blocked with plates. The rest of the upper engine is stock I think, just K&N and descreened MAF. The baffle connector for the AIR thing has a plug on it. I need to do more research on that AIR thing, there is an open hose connector near the firewall over the drivers side rear coil pack on something, I think it's the AIR thing. And there is a hose, about 1" to 1.5", that is just laying in the back of the engine, with no obvious place to go. The engine runs pretty well, no way it's just an open coolant or vacuum line lol. So I need to figure out if that stuff is supposed to be plugged or what, but I don't think it's related to the whistle? I did plug my finger in the hole of the AIR thing, but no change in the whistle. It doesn't feel like any vacuum either.

cyberkill

AIR is turned on only for the first few minutes of the car's being started until the cats reach a certain temperature, so even if you've blocked it off, if the AIR hardware is still in the car and connected via power and to the computer, it may be the source of the sound. I've got more of a whirring noise in my car (2001 with AIR system still in place), and after about 5 minutes or so there's a sudden depressurization sound and then it stops. If yours turns off after about that time on cold starts and don't hear it on warm starts, that may be the culprit.

However...I do also have a constant faint whistle sound. It gets higher pitched as I rev, and it's constantly on, and I don't know what that is. People suggest belts, but I don't think it's that.

Undertow74

iTrader: (45)

if you didnt rip the AIR pump out of the car and just blocked them off at the headers, that is what you have. Especially if you just tore out all the lines and left the AIR pump and Fuse in, it is going to sound louder because the Pump is running with no lines attached

garygnu

cyberkill you mite have a vacuum leak,intake gaskets or map sensor.or a brake booster leak.

bandit-00

iTrader: (2)

It's your air pump. Pull the fuse for the air pump until you can remove the entire assembly. If you blocked off the lines you don't need it. I assume you had the EGR and AIR tuned out?

milburnr

yeah I read some more stuff and checked, it was the AIR pump. I removed it, and the solonoid, and the hoses. Started it up, and did not get the whistle. Thanks everyone!

PS I got some pics of parts that are missing on the sticky about AIR, and it's on an 02 so I have (had) parts that people were asking about.