Subaru WRX Forum banner

Grinding Turbo Noise? What could it be?

19K views 17 replies 7 participants last post by  roadtrip1098 
#1 · (Edited)
Hi guys. I've searched all over the internet to try and find out what is wrong with my car but just can't seem to find anything that fits the bill. Any input y'all could give would be super

My car makes a grinding noise, in any gear/neutral, clutch in or out, at 3500 through 3750rpm. It starts exactly on the 3500 mark and stops exactly at the 3750 mark. It doesn't make the sound at 3400 or at 3800, just strictly between these two points, and it's a consistent sound. It is loud, audible from in and outside the car with no problem.

It sounds as if I was taking a pencil and sticking it in a tiny encased plastic fan, not a roof fan but like an oscillating fan.

Now for the variations:
It doesn't do it when I first start the car in the morning. It will after about a minute but when the car is just first warming up for the day it won't do it.

If I accelerate hard it won't make the sound going up, but when I shift it makes the sound as the tach comes back down.



I'm at a loss right now, because I think my Blow off is causing the problem but my brother destroyed my stock bpv. Hammers, brothers and bpv's dont mix. I digress.

I thought at first that it was compressor surge but the sound just didn't match up, and surge seemed more sporadic and this is constant to a tee.


I appreciate any positive input, thanks ahead of time.
 
See less See more
#2 ·
I don't have any solution for your problem primarily because I'm experiencing the same issue. In my case it happens exactly between 2500-2800 no matter if accelerating or decelerating rpms.

It too sounds like very fast pinging, almost like valve pinging but slightly higher pitched and way too fast for valves.

It happens after the engine is warmed up and usually after highway driving and not it doesn't depend on my driving style.

My mods are simple (gutted uppipe, K&N drop in) and I only started noticing it after putting the K&N filter in.

What are your mods?
 
#3 ·
stage 2 mods were in but this has me freaked out enough that I put the stock parts back on to see if it made a difference and I'm driving 99% stock (w/ gfb bov) with the stock map.

I'm driving it stock to see if it makes a difference, it's been two weeks since I put them back in
 
#4 ·
Do you still have the stock turbo inlet?If you had a silicone aftermarket one it would be real easy to pull it off and use a mechanics mirror and a flash light to get a good look at the compressor wheel and see if you can find any damage to the wheel it self or if its making contact to the housing.Then pull off the downpipe and check the turbine side.Do you stilluse the stock EGT probe?If so check to make sure it hasn't broke off.For shats and giggles you could change the fuel filter,run some injector cleaner, and do the Seamfoam trick.I would run the Seamfoam off one of the inlet nipples so it cleans the compressor housing and TMIC as well as the rest of the intake tract.Also if you have a laptop I would suggest buying a Tactrix cable and datalog the car.Helps find problems like 10X easier.
 
G
#17 ·
I would run the Seamfoam off one of the inlet nipples so it cleans the compressor housing and TMIC as well as the rest of the intake tract.Also if you have a laptop I would suggest buying a Tactrix cable and datalog the car.Helps find problems like 10X easier.

Pop a nipple and let the hose suck up some Seafoam from the can, or pour a little Seafoam into the turbo inlet hose while the engine is running? Give it a little throttle to keep it from dying probably....how much Seafoam would be too much to pour into the inlet hose?
 
#7 ·
Since I have the same issue, I was considering it to be a valid source of the noise too. As a matter of fact when I did the uppipe I missed one or two screws for the heatshield (why so many of them originally? replaced since then) and it was rattling. Maybe one of them is lose, I'll have to check once the ice age goes away in Chicago.

Other then that the car is running great, pulls strong, good mpg, no other weird sounds, no shaking, all liquids perfect, no leaks.

SilasJordan.USF:
Did you remove the snorkel on your car?
 
#12 ·
Oh I didnt know that was a snorkel. My car lingo is limited lol.

So I'm driving up to st pete for a seminar today, and along the ride I notice the noise stops. As soon as it did my car felt brand spankin new, from third it pulled like it was in second.

Hopefully it's permanently remedied :)
 
#13 ·
Same thing, maybe

I have an '05 WRX and I am having the same or similar noise from around 3000 to 3500 rpms on acceleration and decceleration. No engine modifications on the car other than an STI high flow air filter. I was hoping it was the heat shield and not the turbo.
 
#15 ·
so it turns out that it is in fact the turbo, what is wrong with the turbo has yet to be discovered.

Theyre gonna pull out my turbo wednesday and look at the turbine, supposedly it should have some shaft play and be grinding against its casing.

Hopefully the oil restrictor pill caused it and not my b.o.v. so fixing it will be under warranty :D

J.i.c I traded my buddy my gfb bov for the stocker.
 
#16 ·
I finally got a chance to get under the hood this past weekend and as I had assumed/hoped it was the heat shield on the turbo making the noise. The two bolts on the arm of the heat shield that bolts into the shield for the exhaust were loose to point I could practically turn them with my fingers. Tighthened them up and the noise is gone.
 
#18 ·
Had the same noise, snorkel delete, Perrin Recirc Valve just started now that it's -2 outside. I popped the hood and noticed the adjustment on the recirc valve was out about half a turn (think it was a result of rapidly changing temps and the vaccum line pulling on it). Twisted it back to where it should be and think I may have "fixed" the noise. I'll adjust it more later to see what I can acheive.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top