Is Diagnosing My Low Power Issue A Goer?

[Guest Porker]

It's some time since I posted on this forum but I have owned my TDi Alhambra for over 2 years and despite around 15 visits to 2 Seat main dealers, (including a new engine), I have always had a low power problem.

 

It is intermittent and unfortunately the dealers don't have a clue. They treat me like I'm an idiot when I explain that the MAF has been changed with no difference and are convinced that if they hook it up to their 'computer' enough and replace the MAF often enough it will cure it. Strangely enough it never has. So they change things in the blind hope that things will improve. I've had 3 MAFs, needle lift sensor some other valve on the turbo all to no avail all at a considerable cost. When I say intermittent I do mean every journey. Most mornings I start the engine and get the telltale sluggish throttle response. Turn off then on again and its fine for maybe a couple of miles, then it gets all jittery (like a poor electrical connection) and looses loads of power ie maxed out at 40mph and feels like the throttle only works for the first 25% (not good on the slip road of the M3).

 

Anyway, I have lost total confidence in the main dealer and have shelled out 100's of pounds in the process. So I am wondering whether investing in a VAG lead and software would help diagnose the problem for myself? Is it possible to measure sensor output in real time on this system with my laptop strapped in the passenger seat? Strangely for a Haynes manual they describe the turbo system quite well.

 

I have decided this weekend to check all the pipes for leaks and look at the electrical connectors. Is it worth looking at the ECU as I understand there is a vacuum pipe that runs to this?