Screeching Noise! Turbo???

[YerMother]

Got a problem I think!

I have a screeching noise coming from somewhere in the engine which I can hear through the bulk head! So obviously I'm presuming turbo especially when it only occurs when turbo is on full boost past 5,000rpm! Car is running fine and VAG-COM is showing nothing out of the ordinary (Still meeting boost etc.) I have had to TIP off and had a spin of the compressor wheel and all is ok there!

So i'm kinda puzzled I have only just noticed it as I always have the radio on so couldn't hear it, but recently disconnected the battery and didn't have the code for the radio to hand so have been driving around without!

One thing I thought it may be is the wastegate creeping open abit! (Can this Happen?) As past 5k Wastgate duty cycle is at max so wastegate should be fully closed! It is even more apparent in 1st & 2nd where revs build very quickly!

The screeching noise is similar to the noise when boost is build in a high gear (4th 5th etc) from low revs! Which I have been told is air resonating in the compressor housing! (Or something ) The severty of the noise changes, sometimes you can barily hear it!

What you guys reckon?

 

[Feel]

Leak? Have you checked the turbo oultet hose for splits?

 

[dsmithmobile]

Sounds like it could be the turbo if its the same fault as i had the sound was not noticable at lower revs but higher up the rev range i got the screeching sound,upon inspection of the intake you could see the compressor wheels blades where curling over and at higher revs the slight play in the bearing was enough to catch on the intake housing as there was a score mark inside a replacement turbo was fitted and all was well,i hope its not your turbo but if it is then it could be an excuse to replace it with a bigger one

 

[Feel]

Ah - you put the stock TIP back on didn't you? TIP collapse perhaps?

I'm sure that a larger replacement turbo is the last on his mind

 

[The MoffMeister]

yer mother im getting the same thing does it get noisey in the car when you go past the 5000rpm?

 

[YerMother]

I never thought of the TIP collapsing! I doubt it though as there is no drop in performance! Well not noticable anyway! No Leaks mate all is well, it's the wrong kinda noise!

@ dsmithmobile, you get it fixed under warrenty mate?

Bigger turbo

 

[YerMother]

yer mother im getting the same thing does it get noisey in the car when you go past the 5000rpm?

Yes mate! I don't know how else to describe it! It's a screeching noise!

 

[The MoffMeister]

an doesn't pull as hard as it should??

 

[YerMother]

Yea still goes well! Still holding 1.1/1.2 bar @ 6.5k

 

[The MoffMeister]

well im getting same thing but mines not tuned and its been since i had revo trial doesn't seem to pull as hard from 5000rpm? keep us informed if you dont mind as i'd be interested to find out what it is mate?

 

[YerMother]

Is your DV alright? That could be your problem!

Anyone else like to contribute to my problem??

 

[The MoffMeister]

my dv is bran new from forge although i'll strip it later and let you know my findings so wish now i had of kept the old one!!

 

[225]

Search the Forums for Screech, basically once remaped the extra boost causes teh tubine blades to make this noise sometimes. REVO Kev ave a detailed explination somewhere.

 

[YerMother]

my dv is bran new from forge although i'll strip it later and let you know my findings so wish now i had of kept the old one!!

Just push the piston up, put your finger on the vacuum pipe and let go of the piston and see how much it come back down!

 

[The MoffMeister]

yeah got ya!!

 

[YerMother]

Search the Forums for Screech, basically once remaped the extra boost causes teh tubine blades to make this noise sometimes. REVO Kev ave a detailed explination somewhere.

Thats what I was was trying to expalin it sounds like. It's always done it at low revs in a high gear when boost is building but not at 5k onwards

 

[225]

Mine used to do it once REVO'd every now and then, as you say low revs in higher gear.

 

[The MoffMeister]

right stripped my forge dv and all seems ok i think
i pushed the piston to the top put my finger over the inlet bit on top it drops a little as i reckon it should then when you let your finger go it drops back down?? any ideas? bout to take it out for a spin back in ten mins!

 

[The MoffMeister]

no not a difference but mine screams in the higher revs 5000rpm onwards surely someone on here knows thier stuff? no offence meant guys?
as for your info mother, when i done vag com it stated that my waistgate, n80 17834/p1426 tank valve open not sure if this is anything to do with it?

 

[YerMother]

Don't think it is the TIP collapsing as it does it when I spit it into standard mode as well!