Whistling sounds

[WFO731]

Ok, well when I'm at low rpm's my car makes a whistling sound coming out of the air filter and it only does it when im maintaining the same rpm's. Some body know what it is and if its bad.

 

[titogs95]

Sound like it is coming from the turbo.
Go and remove the intake pipe and check for shaft play. Maybe the blade are hiting the inside.... (If you still have the T-25 is a great time for upgrade).

 

[WFO731]

Check the play and there wasn't any play so im guessing that wasn't the problem?

 

[MrBoxx]

I notice you have a 1g BOV. Sometimes the BOV will make a whistling noise. It usually happens to me at around 2k-3k rpms, usually cruising in second or third gear around 20-30 miles per hour. My theory is that the metal valve isn't sealing totally against the body and is letting out enough air to make a whistle. It sounds very much like an intermittent teapot. Weird, yes, but I've stopped noticing it.

If not that or the turbo blades scraping, it may be a simple boost leak. Do a boost leak test just to be sure.