2002 Sharan 1.9 TDi Intermittent power loss.

[dazmac]

Occasionally, and probably only under load, the 1.9 TDi loses power. You can be happily driving along on a motorway for 2 hours then with no warning the car loses the power, I assume its a limp mode as the car will still drive on but with less response.
Anyway, turn off the ignition and it resets. THen maybe 2 hours later, the same again, or it could be every 15 mins for a brief spell, there is no timing period for how often it happens.
This initially happened about 4 years ago and upon reaching my destination some 3-400 miles away with the fault occurring a couple of times I realised that the back box had parted. I assumed it was a back pressure that had caused it? Anyway, no more faults until this year. Same again (not the back box) but the fault is there.

So..... suggestions please?
Its done 88K and nothing serious has been replaced.

[kenney]

I would suggest a fault code read,

[dazmac]

Fault code reads:
17965 Charge Pressure Controller Positive Deactivation P1557-35-10 Intermittent.

Problem has now progressed, 90% of the time it is like driving a car without a turbo.

So, is it....

The MAF? Tor the Turbo actuator arm sticking?...OR the Turbo itself?

Garage beckons tomorrow.... Timing Belt was due anyways

Having done a bit more reading, I am guessing the Turbo, possibly the variable vanes sticking.
Does anyone have experience of stripping and cleaning these, can it be done without a replacement?

[smither01]

If you are still on your original air mass sensor then I would suspect that may be failing given its age and mileage. If it sometimes works perfectly then that at least rules out mechanical wear - which is a lot more expensive to fix!
Good luck

[dazmac]

Thats what I am hoping given the price of turbos.

[dazmac]

Ok, Turbo replaced, as per garage recommendations


MAF meter swapped out for a mates with no difference.

C*ap!

Gutted.
On the plus side, I now know its a pretty easy job to replace the turbo.
Latest code?
17964 - Manifold Pressure Sensor (G71): Open/Short to Ground

[dazmac]

Does anybody know the name of the electrical valve that controls the vacuum line to the turbo?
It is mounted on the bulkhead behind a heatshield in the engine bay.

Last chance saloon as everything else appears to be working.

[kenney]

Charge pressure control solenoid valve -N75-

[dazmac]

thank you
Can this be sourced anywhere other than VW? Or is it a VW only part?

[dazmac]

Kenney, What's the other valve there called?