my03 sti turbo squeel
 

when the car gets to boost in around 4th 5th maybe 6th gear at 3500rpm when the turbo cuts in is gives of a horrible squeel & its definatly not the clutch whats the chances that this could be to do with the wastegate valve not being held shut properly the car has decat 3.5 inch straight through to a prodrive backbox wheter this makes any difference or not only really started to do it after 2 months of the exhaust being on someone told me ( There isnt sufficiant backpressure in the exhaust system to hold the flap shut)

anyone out there help me please

Many thanks
Rob

Did you also fit a new up-pipe?
It could be an up-pipe gasket leak, squealing at peak boost.

Nick

it had a new up pipe fitted with new gaskets and the noise is still there

Wastegate is held closed under the pressure of the spring in the capsule , and also would be down on power . Possible piping from turbo to intercooler leak , leak / puncture in intercooler , crack in wastegate housing but would also result in lower power or the worse thing turbo bearing failure !

bearing failure is what iam fearing it only squeels for about 2 seconds then normal spool up sound, sounds like metal to metal contact but local dealer says nothing wrong dont fancy the thought of metal filings flying about much

It's quite hard to get the air inlet pipe off to the turbo to check the impeller housing to see if there is any sign of the impeller rubbing the housing , may be better to remove the exhaust downpipe from the turbo where you will see the rear exhaust impeller and wastegate flap , then you'll be able to check if there is any cracks between the edge of the exhaust impeller housing and the wastegate in the casting ( have seen a cracked one off a rally car ) and feel the play in the spindle of the turbo , with no oil pressure may feel very very small amount of sideways play in spindle ( push towards the intercooler and the back ) when you put sideways movement on it and when you turn the spindle by hand should not hear any scraping noise's from it , if there is then it's f*!ked (not 100% on scoob turbo's but 15 years on different brand of car ). How many miles and has it had regular servicing carried out / turbo left to cool after a good run /given chance to warm up first etc , if not then that may have been the cause .
Hope this may help you . :)

Thanks for your reply, its got 20,000 miles on the clock been serviced by main dealer since new even allways warmed up and cooled down properly been very carefull with that part of it when the cars up full boost the turbo sounds as sweet as a nut it just the initial bit

Can you hear the noise with the bonnet open and just revving the engine , you will get a small amount of boost on revving it so the turbo will be starting to spin up , have a listen around the turbo and intercooler . If it's a leak you normally hear a long ssh type noise . Have you an atmospheric dv or oem dv ? as i have an atmospheric dv and the piston was a bit sticky and leaked a bit until the boost was more then it fully closed , but that was a ssh type noise . Another way to isolate it would be on a rolling road and listen with a stephoscope on the turbo .
From the mileage and how it's been serviced and used the turbo should not have gone , are you able to record the sound and upload it to the thread , on hearing it may shed some light on what the cause is .

if you have the bonnet open and rev the engine there is no noise at all & i removed the oem dv and replaced it with a atmospheric one have tryed swaping it back to standard thinking this was the problem but the noise is still there i will try and record the sound if i can, someone else on scoobynet also has the same problem as me as he pm me to see if it was sorted his user id was zuby

Take it to the next rolling road meet m8.

Cant think of anything else at present , but as davedipster said above ,then it'll be heard without the car moving so should be able to pin point it . I've heard a good few knackered turbo's now and normally they end up either no boost at all or howling like a police car siren when the spindal bearings have gone . I thinks a spin on a rolling road will show whats up , let me know what was found .

i did have the noise, but since then ive replaced the prodrive exhaust with a blitz and have also put on a hks ssqv. I think its eliminated the noise, or i just cant hear it :wonder: ...

but since you pm'd me i thought i once heard it again, not sure.... :freak3:

Had a similar problem with mine, sqealed when boost got above about 1 bar. It was a small crack in the i/c to throttle body hose. Escaping pressurised air makes a nasty noise.

i Removed the ic the other day just to examine it and the hoses appear to be intact no splits or cracks in it and the ic itself looks ok as i say its going back to the dealer again on wednesday morning for the 3rd time so its up to them again will post results when i find out whats wrong

if you've had the car in the dealer's before and they have charged you for finding the noise then it is down to them to do it and they should'nt charge again for the diagnostic only for the labour and replacement of the defective part .

forgot to mention its still under warrenty until the end of this week

Get it in there before warranty is out and they will have to complete the work , and when you collect it give it a damn good road test to confirm it's gone as soon as you leave the garage , it you hear it in the slightest take it straight back the same day before they close the job card .
I work in a garage and do the warranty claims so as long as the job card is not closed then they can just continue on the same card so the warranty will cover it , if the card is closed and the warranty has now expired they would have to ring subaru customer services to get an authorisation to do any work .

The VF range of Turbo's can squeel when they come on boost. My VF28 does and a mates VF34 also does it. It's more noticable with a decat downpipe.

sounds like an old kettle coming to boil....

Got something that sounds very similar but my car is a 97UK model with OEM ported headers and Sports cat Miltek system.

Noise happens with 2 different turbos, when they are pushing 0.55bar+ round about 3200rpm. Then it stops at about 4500 rpm and a higher pitch noise starts.

It doesn't sound like air escaping I don't think ie leak, but it's not the turbo (unless I've got 2 dodgy ones, and 1 has just been rebuilt) and I'm still getting expected power. 265bhp from mapped standard TD04 with 270ftlb too.

:wonder: :wonder: :wonder:

isn't the MY03 a VF35 ? Mine does it all the time. Totally normal

My old td04 and vf34 both do it.

As Steve says, normal :)

Had a suggestion it might be something to do with the dump valve bleeding air through at high boost - anyone reckon this idea has any legs ?

Nope , mine hits and holds it's boost target perfectly :)

had a subaru mechanic test drive my car with me in it and its perfectly normal i recently changed the downpipe to a decat so i checked the shaft in the turbo and no play so will just leave it at that

My car started making the noise you describe on the way home, only it happens after 1.1 BAR. It's very loud whistle noise and I get the grating sound as well. If we are talking about the same noise, it's not normal.

If it's happening around 3.5K when the turbo is starting to push full boost, it could be over boost with some surge.

I find it hard that the dealer thinks it's normal, unless the the sounds are different between our cars

Where abouts are you?

Anders

Its not a grating noise as such but just a real loud high pitched scream for a split second then disappears its now louder since i changed to a decat downpipe granted to turbo does overboost for that split second it goes right round the clock then equalises to just over 1 bar.

iam up in cumbria if any were near

If yours is over boosting round the clock, my advise would be to have your car remapped. If your hitting 1.7/1.8 BAR on a standard map, you will be having DET and it won't be good for the turbo either.

I'll keep you posted on my findings, I'm going to check all the boost pipes and the hose between the IC and throttle body for leaks.

I'm in Surrey, so not that close.

Cheers

Anders

Had mine in to the dealer today and gave them a test drive and their initial thoughts are the turbo. They have booked it in on Monday to check for any play in the turbo.

It was in the garage last week, when the heat shield failed on the turbo up-pipe. I commented that the oil consumption had gone up since the last service, so may be that was the early signs of turbo failure?

I'll let you know what they find on Monday.

Cheers

Anders

cheers for the info i have just changed the downpipe on my car so i thought i would have a look at the turbo shaft and its as solid as a rock and no oil consumption to report never used at all i have stopped giving it a handfull of throttle until i get it mapped by andy f next month