Hey everyone,

So I have an 04STi and I've been having a high pitch whistling sound coming from the engine bay when driving. Specifically, when I'm in high gear at a lower RPM, it sounds like there's some kind of hose leak perhaps? At first I thought it was just my SPT intake but they're two completely different sounds. I don't know, sometimes it feels like there's a lag in response when I press down on the gas pedal as well. Any ideas what this might be? Thanks for your help! :]

 

Check the Hose clamps and hoses from the Turbo to the IC and the IC to the TB. it would be a good idea to check all vacuum hoses, BPV hose, and so on.

 

I'll definitely do that when I'm home. 2 of my hoses cracked from the boost control solenoid but I replaced those; thought that was the problem but the air leak is still there. Thanks!

 

Anyone else have an idea?

 

Bump!

 

theres a machine for to find leaks..take to a shop liks gst to have them run a boost pressure test or something like that..if theres a leak you'll see i come out..its like this powder substance..

 

Took it to Garage 1 and they tested for leaks but found none. Said my clutch was making the noise but I got that replaced and it's still there. Not sure what else it could be.. maybe my intake?

 

Bump! Please help!

 

unlikely, but check your up pipe gasket could be an exhaust leak?

 

So much work to get to the up pipe x_x but yeah, maybe it's an exhaust leak. I'll check out my dp > turbo gasket.

 

if there is lag it would be before the turbo... well in theory... in my head... after the turbo it would have already spun the turbo up and then leak...