TT, 225, 2000, APX engine - Lack of power

[The Specialist]

Have you checked Crasher the turbo your self for free movement just to rule it out yourself, does the mechanical bypass valve work check with a myta vac will prove the diaphragm is OK if stuck open will allow the boosted air to bypass the turbo charger.

[guerrra]

just a todd, the pressure regulator of the fuel rail is working ok, does it gives more pressure as you press the acel. fast?
i had that problem on some cars not audi tt, that were not reving fast, the vacum that made that efect was not working , new reg and ok, hope im not ading the confusion!
guerra--

[Crasher]

I haven't checked the turbo for myself, the customers seems unwilling to keep paying out and I can only grab hour or so chunks on the car once a week. The first deep test I did was to pump the wastegate diaphragm to see if it was free and smooth and it was.

[The Specialist]

Crasher to properly diagnose and repair this vehicle more time must be allocated to sucessfully fix the fault, more time will fix this.

[Crasher]

Ohh absolutely agree old boy, more money can fix everything.

[The Specialist]

Crasher if you get this vehicle back in had a 1.8 20 valve turbo with very similar boost problems like you had. Cut a long story short the internal wastegate had fell apart its only as big as a 10p piece this how ever resulted in all the exhaust fumes to bypass the impeller and straight down the exhaust system, might help might not.

[Crasher]

I have resigned myself to removing the turbo, a deeply unpleasant job on a TT. Thanks for the pointer.

[Ned]

 Hi Crasher, just a thought we have just put in a AJL 1.8T engine from audi in a A4 Quattro (due to lack of oil and seized head and no compression) anyhow the guy said his car has been flat for ages and Audi looked at the turbo with it running and saw the impeller rotating because it read lack of boost on VAS but he did not want to pay the money so just ran it, then with lack of servicing it bit him big time, when the turbo was off the engine I noticed  that the nut on the intake side of the impeller was loose and basically the shaft had sheared but if you spin the exhaust side fast it will contact enough to make the intake spin. and i know its tight to get at but this check may save you a bit of time, we`ve also had a golf with no vanes left on the intake too debris dropped down piped during a job at a fastfit place........But the best thing to remember is you don`t have to take the work on there is always easier money made thats what the dealer`s for!!

[Angus]

Crash

That reminded me of a job [on my accountant's] 1.8T A6 a few weeks ago.  The oil pressure relief valve had come loose, fallen out and then he drove it 20 miles to see if the oil light would go out.....  [It didn't!  The exhaust cam seized, broke the chain, stripped the belt and it... er... "stopped."]

When the engine was being replaced; on that one too, it was found that the nut had come off the turbo's compressor turbine and mullah-ed the vanes.  [New engine and new turbo... ]

After fitting the new turbo, he said that it had never, ever, gone like that before.....

Have VAG got a problem with these turbos?

[Crasher]

Hi Ned, I have this problem-when someone throws me a weird one I can't let go, it is this sort of challenge, testosterone man thing. I have to fix it if it kills me, I can't explain it further than that.

Angus, my accountant drivers a Mundaneo and if it went pop I couldn't give a toss!