I have an 03 Gsi, 71k, which developed a boost problem while driving home two weeks ago. Just under 3k rpm and the boost seemed to hesitate then kick back in again, and repeats this to the red line in 3rd, 4th, and 5th.
I had the car diagnosed (not VX yet) and was told the problem lied with the sensor which has a vacuum hose connecting to the top of the actuator (no other read codes showing). When this was swapped the car over boosted and went into limp home mode. I'm been told in short the turbo is knackered.
There is occasional white smoke from the exhaust when left idling for 20mins or so. This disappears pretty quickly. And there is slightly increased spooling sound when accelerating.
I've checked the wastegate today which seems to be moving freely. The vacuum hose to the top of the actuator has a few tiny splits in the top but these are after the clip.
Recently swapped for new parts - MAF & coilpack.
I've had it out today and the fluctuating boost issue is nowhere near as noticeable but it still feels a little flat.
Can anyone help me pinpoint the problem? I don't want to shell out for a new turbo when I'm not convinced that's the right answer.
Thanks, suggestions / fixes greatly appreciated!