Ok guys, I notice that my car (02 wrx) is making a weird noise coming from the passenger side where the DP would be. It sounds like it is leaking but I checked and there doesn't seem to be a leak. When I slowly step on gas I would hear a fluttering noise kind of like turbo surge, and when it reaches higher RPM around 4k and up there'll be this high pitch noise kinda like a Vtec sound but really loud and again coming from that same area. Anyone who knows what could be the problem lmk thanks.
Sounds like a combo of wastegate flutter (normal, don't worry about it) at partial throttle/low boost and an exhaust leak under full boost. If the sound is really loud and sort of sounds like a cricket on crack, you probably have a manifold/uppipe joint leak.
It's pretty common to find leaks there due to the design. Grimmspeed has extra thick gaskets that supposedly help fix this problem. The best way to ensure that you get a leak free connection is as follows: 1. loosen all joint connections at turbo, uppipe, manifold, and head. 2. tighten the uppipe/manifold connection FIRST 3. tighten everything else
weld it shut! really you can just tune to take care of it but i wouldnt worry about it to much your probably seeing this now as the air is getting colder so your WG is trying extra hard to keep the boost down at the boost target.
If it sounds like a helicopter under the hood by the turbo, and you only get the sound during partial throttle boost, it's WG flutter. If the sound gets louder or is a "whine" or "hiss" type of sound, you either have a leak or your turbo is on its way out.