There is a high pitched screaching coming from my car periodically, and it's not my brakes. It almost sounds like there is something in the turbo that is messing **** up.

So at first I thought it might be my brakes, but I have driven with my left foot on the brake and it still made the noise. It sounds like it is coming from forward and right when I am driving my car, right where the turbo is.

I also thought it could be belts for some reason. I recently replaced my power steering/alternator belt but I checked the tension and it is fine.

Anyone ever have this problem or have any idea as to what it could be?

TIA,
Nick

 

what are ur mods?

 

is it really loud or do you have to be listening for it? i get a little high pitch whine from the turbo if i listen for it(not from the turbo spooling up, obviously). i can't hear it when i'm driving though. it lasts 2 or 3 seconds and goes away. does it do it when you are idling? if so open the hood and listen for its exact location. sorry i can't be useful.

 

Engine related mods:
APS Performance Programable ECU (Uni-Chip)
APS 3" Full Exhaust (inc High Flow Cat)
APS Hi temp/Hi flow hoses
APS Cold Air Intake System
APS TMIC High Volume Dual Vent Blow Off Valve
APS TMIC Cold water spray system
JUN Lightweight flywheel

If music is playing softly, you can hear it. It's definitely not good and not normal.

 

hhhmmmm i'm gonna take a stab in the dark and say turbo bearings???? hopefully someone that has a better idea will ggive you a better answer. sorry i can't be more help

 

does it only make the noise under load? like when the turbo is spooled and it producing boost?

 

You state that it makes the sound periodically and not continuously. Does the sound occur more often when the engine is cold? I'm just trying to rule out the drive belts because sometimes they will need to be re-adjusted for tension after being replaced with new ones.

--
0==WW==0
"…axles of evil…" - george w. bush

 

It's not a constant sound. It's also not at any particular RPM, but I notice it between 2500 and 3500 the most. It is usually when the engine is under load, as I cannot get it to make the noise while sitting in place and just revving my engine. It has done it right after I stopped at a red light though, so I'm baffled.
When my turbo is spooling alot, I cannot hear it. All I hear is all the air being sucked in. If I am just barely spooling my turbo (not to the point where it is sucking in alot of air), I can hear it. I also hear it when I am off of the gas to decellerate.

 

Does not occur more often when the engine is cold. I also already checked the tension on the belts and the once I had just replaced was a little tight so I backed off the tension bolt a little bit.

I would probably even say that it occurs more often when the engine is hot.

 

i'd check at the gaskets for a leak...

when you said "under load"... i had a similar thing... i played around with a custom made uppie to a downie.

for laughs, i had it dynoed... as the dude revved it to redline, around 3rd gear, this LOUD noise would come up. almost everyone said dead or dying turbo.

even had a couple of the i-speed dudes ride in it and said turbo...

eventually i got too paranoid of having these items to i put the oem parts on...

so off to GB motorsports to put the stuff on. then they show me the gasket between the turbo and the downie was just eaten up...

they install new ones on and i never had the noise again... turbo never gave any issues for the year or so i had it...

 

you're sure it isn't gearbox noise?

 

I just drove it again and it doesn't do it at all when cold, only after being warmed up.
I also noticed that it does it more when I am off the gas and just slowing down due to engine speed. A point it almost always happens is at 3250 rpm and I was at about -.39 to -.41 hkpa boost according to my turbo timer.

If it was gasket, why would it come and go as the engine speed changes?
For example, I can be going 30mph and downshift to 2nd. Let of the gas to decellerate and it will make the noise at something like 3250 rpm, 2750 rpm, and 2250 rpm (just examples). It makes the noise for a second or two and then goes away then comes back.

Thanks for all the help.

 

bump.

Any other ideas other than it being the turbo or gaskets?

 

Well, until your last post, I thought it might be a wheel bearing. Have you played with it in neutral?

 

When I clutch in/put it in neutral, it all goes away.