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Hi,

I have been having issues with my check engine light. It keeps throwing P0299 (turbo charger underboost).

I took it to my Audi dealer and they have replaced the valvecover gasket , all three turbo valves and the camshaft adjuster tensioner & seal. Also replaced the pipe that connects directly to the turbo (don't know the part name). I realize that the oil leak isn't directly related but they found it and had to fix it. They thought it might be related.

These repairs have been done over 3 visits. Each time they say its fixed, I leave and drive about 40kms and the light comes back.

They now are saying its the turbo that needs to be replaced but really don't seem sure anymore.

It seems reasonable that it could be the turbo but I wanted to check here before doing it. Anyone else have issues like this?

There is no loss of power, car is driving great.

Any help would be appreciated!

2003 Audi A4 Quattro
140,000 km's

chances are it probably is the turbo, I feel like Audi knew this but replaced everything else to take your money.

the only real way to tell yourself is to find someone with vag com and log actual vs requested boost levels and see whats up. It could just be somthing as simple as a faulty wastegate actuator which in audis world means turbo replacement, if someone has a junk turbo you could just swap actuators and have it fixed for a fraction of the cost.

If it turns out you need a turbo, I'll sell you mine. Boosting perfectly (recently had it tested). I'm looking to go KO4 anyway.