"Whistle while you spool" problem..and a few others..

[paranoidTSi]

Ok here's the issue, I recently got a 3" downpipe installed, but right before I installed it I noticed the turbo would "whistle" (like putting a straw out the window of a car at a angle) but it has kind of a whine to it, but it will go away once above about 3.5K (either it goes away or I can't hear it over my BOV/Exhaust). What might be a cause of this? The turbo has NO shaft play as of two weeks ago. I don't really think its even the turbo its coming more from the passenger side than the driver side.

Also, periodically I will hear a popping noise sometimes in front other times in back, its random, sometimes it happens when I hit a bump, other times its on a turn. I can't figure out exactly what is causing this as it is COMPLETELY random. Its like pushing out a dent in a car noise only not very loud. Is it possible its the frame? I figured it could be the cv axle, but the front ones were just recently replaced. I can't for the love of god figure it out. If its the frame what can I do to fix it?


These maybe minor problems to some, but to me ANY noise that appears that wasn't there before ANNOYS the piss out of me, including interior rattle.

 

[plymouthtalon]

Does the turbo whistle increase in pitch as it spools faster? Mine made a noise that got higher pitched as it spooled - it always sounded like a police siren that was really far away. The turbo had no shaft play at all, but a week after that the spool noise and BOV noise completely stopped - the turbo just froze up and I had to replace it. Have the turbo checked if this sounds like your problem.

Not sure about your popping noise though, sorry.

 

[paranoidTSi]

It goes away at higher rpms, it doesn't get more high pitched, it whines, gets louder, goes away. My turbo better not give out on me damn-it!

 

[TurboSpyder99]

mine did the same thing on the stock turbo, but I think I noticed it more with my downpipe. It was a weird super high pitched nose on top of the spooling. I was also running a goo 16-17 psi on that turbo for a good almost two years like that and when I swapped in the new turbo the stock one was fine. So at least in my case it didn't hurt anything, but I still am not sure what it was.

 

[Enigma_Man]

It could possibly be a loose / cracked vacuum hose somewhere... Those can whistle.

I'd build an intake leak tester.

-Jesse

 

[JessesTalon]

those pops could be small back fires... going off early in your exhaust or later... therefore you can hear the sounds sometimes in front of you sometimes behind u, I have the same problem (3" turbo back no cat)

 

[TurboSpyder99]

Enigma Man brought up a good point. When I put on the new turbo I checked for leak and found a huge one at the throttle body, so that might have been my noise.

 

[FASTSPOOLINGST]

when turning and hitting bumps=bad cv's check your boots for leaks.

and your turbo is bad or u have a huge leak. I had the exact same whistling sound when my turbo was bad. I increased the boost on it and it only lasted about a month or two longer. I checked for shaft play with it on the car, the turbine was fine (seemed fine anyways), it had no play from side to side, or in a circular motion. After i swapped it for my evo turbo, when it was off, the shaft would go straight back and forth about a half an inch. you could also see where the turbine wheel was grinding on the compressor housing, it cut a line in it and the turbine received a accidental clipping job. .

do a leak check. ref: vfaq site

 

[2GeNTSi]

I dunno I had these weird noises coming from the rear as well, it wasn't backfire cause I know what that sounds like. I inspected the rear one time, checked out all the boots and everything, nothing was loose or missing. But when I replaced my shocks and springs, I never heard it again.

As for the downpipe, I'm pending my installation right now, just waiting on the gaskets and bolts, hope this doesn't happen to me when I install it. I get boost creep as well, with my current mods it goes up to about 18psi, it might be incorrect because when the cars off, the needle rests a little above zero on my boost gauge.

 

[Mr. LEaKS]

check your intake for leaks maybeit could be a loose vacum hose. It happened to me too. i thought it was my turbo but then i put tie's on all the intake lines and it went away. My turbo also had no shaft play.

 

[tsunari]

Don't mean to bring this thread back from the dead or anything . . . but the turbo isn't supposed to 'whistle' when accelerating? I'm on a stock T-25 and I think mine has always done that (well . . .after a K&N, cut dump tube, 3" exhaust, recirculating SSQV, etc . . .)

I figured I was just sucking so much air in that it was just the 'noise' of the turbo spooling up . . . Am I wrong?

check your intake for leaks maybeit could be a loose vacum hose. It happened to me too. i thought it was my turbo but then i put tie's on all the intake lines and it went away. My turbo also had no shaft play.

 

[Attack Eagle]

Don't mean to bring this thread back from the dead or anything . . . but the turbo isn't supposed to 'whistle' when accelerating? I'm on a stock T-25 and I think mine has always done that (well . . .after a K&N, cut dump tube, 3" exhaust, recirculating SSQV, etc . . .)

I figured I was just sucking so much air in that it was just the 'noise' of the turbo spooling up . . . Am I wrong?

Mines always done it too, and this is my second t25 and it sounds the same.
I need a new BOV though my 97 plastic grenaded the top off and my dad had the car so he reassembled it sealed the edges with JB weld and put small screws thru the edges. Seems to be ok for now until I can get a 1 g and a brode UIP

 

[tsigrl2016G]

did any of you, with the whistle sound, notice the it whistle after you'd let off the gas pedal? I have this whistle that started a couple months ago, it sounds like it's coming from the front passenger side...at first i thought it was my bov, but then i thought nothing of it. Til i read all this! If i'm at a stop, and then i start to accelerate-but if i let of the gas, i hear this high pitched whistle, kinda like a metallic echo-whistle. I have a big 16G and i checked for any play while it was still attached to the car, and it spun fine, i did notice a tiny line inside the turbo in front of the wheel, though. I'm doing a leak test for different reasons though, so mabye it's just that. But can that really be a sign of a turbo ready to go??? I really don't want to buy a new one...and it seems to be fine for now.