RB20 Stock Turbo Sound

[quadracer111]

That doesnt sound like a boost leak it sounds like a rabbit being eaten alive!

Yeah.. It doesn't sound right.

[Slider15]

I assume there is no way to check for shaft play without taking the turbo out right?

[Skym]

Put ear on podfilter when engine is at idle (should hear a sucking sound). Should get that same sucking sound but slightly louder when accelerating up to around 0 on boost gauge.

It could be intake airleak (piping, BOV flange) or turbo itself. Without doing the intake hose clamp check (tightening them up as much as you can, checking for cracks in joiners, then drive), checking for turbo play it's hard to say.

If you can fit dial indicator (to check play) onto turbo with turbo mounted on engine. But it should be obvious by hand, as compressor wheel should touch compressor housing. If on exhaust side, harder to check.

But it could be a exhaust leak on turbo to exhaust manifold joint, as it seems to happen under full throttle, higher rpm. Plays the gasket like a reed in a instrument. If this is the cause, the locking tabs are probably not there to stop nuts coming undone or gasket has blown.

[Slider15]

If i were to make a pressure tester which pipe would i put it on in order to pressurize the system?

[Slider15]

So i made the pressure tester and found a couple small leaks so i fixed them but that didnt fix the sound. The sound is coming from the passenger side of the car so i assume it is coming from the turbo. It really does just sound like air leaking out so is there anyway the turbo gasket could be ruined or anything like that?

[Slider15]

If i remove the heat shield and the necessary piping to get my hand down near the turbo is there enough room to check for shaft play? I really need to figure out what this whistling sound is.

[Skym]

From what I can remember, of last time those pipes were removed, there's enough room (make sure compressor wheel doesn't touch compressor housing when turning compressor wheel by hand). On my cars stock turbo it was obvious that bearing had failed on compressor side as whistled at first, then made a wacking sound. Exhaust side of turbo was ok and exhaust wheel was in one piece.

Have to remove rubber intake pipe infront of turbo (from MAF to turbo), intercooler piping above that in engine bay. Make sure you cover up ends of intake piping (some use rubber gloves or similar) so no bolts, dust, etc gets into stock SMIC or intercooler piping.

[Slider15]

Ok thanks, i will try that this week hopefully.

[Slider15]

New info. So i was going up a long hill today in 5th and noticed that my boost gauge was reading just at the line between 0 and +7 but there was no whistle sound. I didnt understand so once i got onto the flats again i punched it and there it was again. Any new ideas as to what this sound could be?

[Slider15]

Just so everyone knows, i found the problem today. I was missing a nut on one of the turbo inlet bolts. I put a bolt on it and poof, the whistling is gone. I can still hear a leak so i think the gasket needs to be replaced so once i get some funds i will order a gasket kit and do them all. Im just excited it wasnt the turbo going.

[steveo1502]

Awesome, always good when it a easy fix

[evolution23]

Just so everyone knows, i found the problem today. I was missing a nut on one of the turbo inlet bolts. I put a bolt on it and poof, the whistling is gone. I can still hear a leak so i think the gasket needs to be replaced so once i get some funds i will order a gasket kit and do them all. Im just excited it wasnt the turbo going.

was just going to tell you this. I just had my manifold gasket replaced as my studs were snapped and it was leaking bad. When replacing that we noticed 1 missing bolt holding my turbo to the manifold and 1 was loose, gasket was blown out the corner as well. after replacing snapped studs, missing bolt and both gaskets, higher pitch sound is gone as well.