Odd loss of power Mk3 Tdi

[sparkie]

Just wondering where to start looking, I have a Mk3 Tdi, and recently it has been misbehaving, acceleration is a little slower than before, and, whilst I can hear the turbo whine as it get going at about 2100 rpm the car suddenly loses power, especially when it is hot going up a hill, and I feel like I am in 'limp-home' mode.

My suspicion is the intercooler leaking somewhere and dumping the pressure, but where should I start looking, the intercooler is buried behind a load of plastic, are there more likely places to look?

[Ryeman]

By odd, I assume you don't mean occasional.

[sparkie]

Odd as in unpredictable, some days it is really pronounced and can barely get up steep hills, others it races up them, no sense to it' except, I think, it does it more when then engine is hot

[Ryeman]

Sounds like something sticking .....could it be a dirty egr valve.
start with the easy to get at things IMOIMO

[sparkie]

Blanked out the vacuum hose to the EGR, and it's still happening! Is there something else I am missing?

[sparkie]

This is really frustrating, just had a service, nothing found by the mechanic, no hisses from the hoses, with the vacuum hos blanked off, I assume the EGR valve is not opening, but the problem persists unpredictably...

[Ryeman]

This is really frustrating, just had a service, nothing found by the mechanic, no hisses from the hoses, with the vacuum hos blanked off, I assume the EGR valve is not opening, but the problem persists unpredictably...

Sounds like the service div didn't try all that hard.

[Gigitt]

I know it's a Couple of months old..

Sounds like a boost hose leak to the N75 valve, or faulty/sticking N75.
Have you scanned it for error codes?

[lynnos]

Hello sparkie, can you come back and tell us how your problem ended up if it has.

[sparkie]

Sure thing, lynnos. So far I have had the diagnostics checked, and no code is being thrown by the management system, I have totally removed the hoses and intercooler from the turbo cleaned and inspected the pipes and hoses, and can see no cracks, tears, etc. The intercooler was a a little clogged up with crap so that's all clean now. It is still an intermittent fault, it seemed to be OK for a few weeks, lots of boost going up the Hinterland hills, but then suddenly I'm in the crawler lane barely getting up hills it sailed up in 4th 2 days before. I can hear the turbo spool up, feel the boost (though it's perhaps not as strong as before) and then suddenly the torque drops and I am scratching round for gears on a hill.

I'm only a basic mechanic, the turbo scares the **** out of me, so I'll spend Sunday looking around at where the N75 valve and hoses are and what condition they are in