Possible turbo whine when cold?

[RLyons]

My 1M fr tdi seems to have developed a whining noise when the engine is cold or has been sitting for more than half an hour or so. It is not a very loud noise but is noticeable to me (perhaps not my passengers).

Once the engine temp needle gets near to 90 it goes away.

The noise seems to be related to turbo speed, I can hear it when not accelerating very hard or when revving in neutral. If I put my foot down it disappears - i.e. seems to only be when the engine/turbo is under part load.

I am hoping it is a belt or alternator etc....any ideas on how to diagnose?

Once fully warmed up there is no unusual noise and the car seems to pull as normal.

PS - I'm on 65k and had an oil service 2 months ago on 61k.

 

[RLyons]

Bump - any one got any ideas? It seems the noise is less noticable from otuside the car / windows down. All I can hear with the windows does is the normal turbo pssss....?

 

[smiff]

I changed my turbo back in march for this reason ive done 1100miles and its apearing again not good turbo seams fine it was a recon so luckily has 12months warrenty

 

[RLyons]

Thanks for the reply, couple of questions...

How loud was your noise?
Was it only when cold?
How many miles had you done? Seems odd that's its back after nearly no miles! Unless they didn't flush the oil when they changed the turbo?

 

[smiff]

The original turbo had done 90k all oil was changed new filter ect correct pd oil. The noise started out as a low pitch whistle that would only last for a little while at around 1500rpm to 2000rpm then started to get louder but would still only happen around the same rpm but also when warm no performance difference was noticeable or loss in mpg

 

[RLyons]

The noise seems to have been the same for the last 3-4k, more of a whine than a whistle. Only on 65k and the last 15 have been by me (babying the car until warm and cooling down properly) so I feel turbo failure is a little premature! I have an MOT and oil service in a few weeks and will ask them to have a look at the turbo.

Cheers!

 

[smiff]

After a chat to turbo dynamics yesterday they said it could be down to the head to turbo gasket they sort of talked themselfs out of a hybrid sale so it must be good place to start

 

[RLyons]

Any joy smiff?

I changed my oil for some properly expensive stuff but it has made no difference to the noise, just made the engine run and sound smoother.

 

[smiff]

Yes plenty of joy for me ive gone to the md515 hybrid mate but i have read on here that the sound is normal as long as the car is boosting right i wounldn't worry about it i thrashed mine right up to change and the turbo was fine took it out no wobble or anything. Sometimes i think people get paranoid when they read stuff on forums just drive it till it blows then at least you know its broken.Other than that its off with the turbo and send it to be checked.

 

[smiff]

Oh yeah you could take the intake pipe off to the turbo and check the play in the shaft any more than 1mm in any dirrection could mean problems but they do move a little due to no oil preasure

 

[RLyons]

Cool, glad you said that - I am definitely one for being paranoid about cars! Will just leave it and see what happens. Wouldn't mind taking the boost pipe off and checking for peice of mind - how easy is it to do that? I've never seem my turbo properly but surely it can't be that hard to get to?

 

[RLyons]

Also - how is the hybrid ? What other work have you done to your car?