PD150 Turbo finally let go

[Shani]

As above my PD150 turbo finally let go. The car has had a CC phase 1 for about 2 years and has done 35k with the remap (60k in total).

As mentioned by others on the forum, my turbo developed a loud police like wail on start up from cold some 3 months ago but this would quickly disappear after a couple of minutes on idle. Car would drive normally.

However the other day the siren noise wouldn't go away and there was absolutely no boost pressure. I have a boost and ScanguageII fitted.

I Limped the car to my mate's garage on idle effectively. Was bricking the fact that the turbo might completely let go and at best the engine may start to burn up oil and I would have to stall it by dumping the clutch whilst in sixth gear. Longest 3 mile drive of my life!

When my mate got the turbo of he said there seemed to be very little play in the bearing and not very much oil in the intercooler and pipework. He's still convinced it's turbo as the car had an oil change service two days before turbo went and my mate and I both went over the pipework to check for boost leaks. Turbo is now off for an exchange unit. Will let everyone know how much it costs.

Considered hybrid treatment but can't justify the cost of it.

What surprised me was there was absolutely no fault codes flashed up for this on my ScanguageII or on VAGcom.

 

[aBoijj]

Why would software pick up on a fault that's essentially entirely mechanical...?

 

[Husbandofstinky]

It begs the question 'why did you let it go on for three months!?'

Cost is not the issue as obviously its a total false economy.

There are other ways and it gave you three months to have time to sort things out.

 

[nick9one1]

Why would software pick up on a fault that's essentially entirely mechanical...?

I agree, you wouldnt expect VAG Com to tell you if your exhaust was blowing, or the tread on your tyres was low.

 

[Shani]

It begs the question 'why did you let it go on for three months!?'

Cost is not the issue as obviously its a total false economy.

There are other ways and it gave you three months to have time to sort things out.

It went on for three months because it would only happen on start up from cold. After ignition about 10 secs later it would wail for a short period. The wail would then die away within 2 minutes. During this period boost would maybe go up to 2 to 2.5 psi bwforw dying away. The car would then drive normally without any other excessive noise.

Other than this noise on start up only there were no other symptoms - no excessive fuel or oil usage. The car performed perfectly fine. So there really was no reason to suggest that we needed to change out the turbo.

In honesty my mate and I were both surprised at how little play there was in the bearing when the turbo was taken off - it seemed to be fine. Both turbine and compressor blades were fine and the oil feed pipe was clear of debri aswell. There was also very little oil (not more than expected for a tdi) in the intercooler. Again all things don't suggest a turbo failure. Yet it was spinning but producing no boost.

And it's not like my mate doesn't know VAG engines - he recently had to change out the turbo on his A4 2.0tdi where the turbine shaft had actuallt snapped!

 

[Shani]

I agree, you wouldnt expect VAG Com to tell you if your exhaust was blowing, or the tread on your tyres was low.

I would've expected fault codes if the engine was performing outwith parameters. For example if boost delivered didn't match boost requested (within some tolerances).

 

[James_R]

The likelyhood is that the turbo is blocked up with soot and carbon thus making the vanes stick which would mean everything would act as normal but the boost cannot be produced or varied. Strip it down an have a look inside and if the shaft on a turbo snaps is a sign of low oil pressure.

 

[UncleFester]

I'd have been inclined to do a VNT cycle with VAGCOM first, also checl the vaccum actuator line, these are prone to catching on the heatshield and splitting.

 

[Husbandofstinky]

Other than this noise on start up only there were no other symptoms - no excessive fuel or oil usage. The car performed perfectly fine. So there really was no reason to suggest that we needed to change out the turbo.

I couldn't have left it, and it would be on the ramps until repaired or replaced.

Just couldn't take the risk.

You were obviously fortunate that it didn't let go in the major fashion.

 

[Shani]

Finally got the car back last night. Treating it with kid gloves at the moment. Apparently the turbo shaft bearings had gone hence the police siren noise. Final cost was less than £550 for an exchange unit supplied and fitted. Not as bad as I was expecting but still not something I wanted to have to fork out for.

Car just a bit smokey at the moment as the residual oil in the exhaust system (not much of it) is burnt off.

 

[Murf]

New turbo for me too, its sounding like a siren & overboosting on the motorway.
Where did you get your turbo from?