Whistle
 

My daughters 02 1.9 Turbo diesel has just developed a whistle. It is throttle dependant. When I say that, I mean I gets louder as the revs increase. It sounds to me like an Air leak somewhere.
It does it if you rev it stationary on the drive and it does it as you drive. I can hear it as she pulls away from our house. I have checked all round the turbo and associated pipework for leaks induction and output side. I cannot find anything obvious. It does not effect power which if it was on the output side of the turbo I would have expected as it would not be delivering the correct amount/pressure of air.
It does not lack power in any way however she tells me it is using a little bit more fuel.

Any ideas would be appreciated as usual.

Check for play on the impellor in the turbo, it could be the beginings of turbo failure.

Thanks for that, I have checked for radial and axial movement and it seamed fine but I will check again. It does sound more like an air whistle as opposed to blades rubbing but appreciate noises can be deceiving.

I have just checked the turbo again and can not detect any expensive play either axially or radially. Listening carefully it appears to be coming from the rear centre of the engine which is where the turbo sits.
I also removed all the flexi pipework small tubing etc to check for splits. Everything checked out fine.
I guess for the price of a used turbo its worth a punt as its now driving us nuts.
As I work away, I did not get the chance to check until the week before Xmas so did not want to get hold of a used unit as I had no time to fit it and I go back to work 29th untill 14th Jan.
I will source a used turbo on my return.
Any one out there breaking one for spares???

All the best for the New Year

Could it be a cracked intercooler?

That had crossed my mind too but the noise is definitely coming from the rear centre of the engine !!!!

check the small hoses around the boost controller valve and the vacuum reservoir tank, also the boost controller valve itself.

Thanks for the reply.
I have done, I have checked all the small tubing and valves. I even sprayed soapy water all around to look for a leak and found nothing.

don't spend good money chasing this. check the throttle stop housing o ring (sometimes called throttle body...WRONG). can go flat with age and leak.

have you checked all inlet manifold studs/nuts are present/secure, is egr valve tight?