Turbo dying?

[Ibiza Dan]

Right,
Was driving down a private test track yesterday for a bit, pulling full boost and by the time i had slowed enough to hear my turbo it was making a "different sound".
Symptoms.

1.Still pulling full boost
2.No increase in noticable smoke
3.New siren type noise coming from turbo when (throttle dependant)

Now i would expect the noise to have changed slightly since i put my catch tank on as i would think there would be less **** in the pipework therefore making a different sound. But just wanted a second opinion really.

Thanks people.
Dan

 

[glynnd]

The police siren from under the bonnet usually confirms your turbo is about to fail.
Thats what happened to mine
Glynn

 

[glynnd]

And for gods sake if it is dont drive it any further, you can draw all the oil from the sump into your engine, luckily I caught mine just in time after i decided to drive it home
Glynn

 

[Ibiza Dan]

How would the oil get drawn from the sump ?
Yeah ive just gone out and checked for maybe a lose hose or something but all looks pretty good.
At a standstill, if i rev the car you can hear a siren type noise as the car goes back down to idle revs. Will i notice play in turbo or something if i remove it?

 

[glynnd]

The engine will be drawing air as normal throught the intake. The noise from the turbo could the bearing has failed and mean the comp wheel is now catching the inside of the comp housing. Any movement that excessive will destroy the oil seal and allow oil to be drawn into the intake and straight into the engine. It can empty the sump in a very very short time. Oil does not compress so even a small amount in with the air will bend a rod or could damage the crank bearings. Not to mention bits of metal going into the cylinders
Glynn

 

[glynnd]

If you take the turbo off then yes check the shaft for movement there may be lots.
A very small amonut is normal, alot is not.
Glynn

 

[glynnd]

Just one thing to add before you take the turbo off.
If the Ibiza has a freewheel on the alternator like the leon has than revving the engine from idle up to say 4000rpm and back down, then you will get a siren type noise from the freewheel. But that is nowhere near as loud as the noise when the turbo is going!
Glynn

 

[Robb1990]

What exactly is the sound? Ive got a gentle whirring noise behind the diesel sound most the time, but i wouldnt say is like a 2-tone siren sound.... more of a whurrrrrrrrrrrr which gets slightly louder as the rev's increase and the induction/diesel noise then drows it out up the rev's. its been doing it a while, so it doesnt seem 'on its way out'

 

[Ibiza Dan]

No its a new noise that i would have noticed for sure if it was the alternater but thanks for the ideas!
Im gonna pull the turbo off and have a look inside, i have a spare somewhere knocking around so could put that on whilst this gets reconditioned i guess.

 

[strugers1]

my car has been making the siren noise for 30k now, and still boosts 1.6bar ok, although i am taking it easier now as hybrid on the way
my old golf tdi did it too and that ha 180k on the clock, like glynn says think its just where the fins are catching the casing of the turbo