Roderick

I have an Allroad 2.5 TDi Tiptronic 5 speed 2002 which has developed a very annoying problem which has caused 2 garages untold grief. My car will go into limp mode when in 5th at around 70 mph or 4th when around 55 mph when start to go up a slight incline, not even a hill just a slope!

If I change down before I know the problem will happen then with increased revs the problem does not occur. So it is possible to avoid the problem however sometimes while overtaking at high speeds it has done it or even when slowed down for traffic, so very difficult to pre empt all the time.

The garages cant find a fault code and if you turn off the ignition and restart then the problem has disappeared so making life even more frustrating. Has anyone heard of this problem? Do you have any advice or help to offer? Thanks for taking the time to read this. Rod Smith

ricam78

Found this on another forum in regards to a similar issue:

OP'S issue:

"I have a problem with my T4 2.5TDI. My vehicle in general operates as normal but when driving along a motorway after some time the power reduces and I can no longer maintain speed up hills. This is either a turbo or power system control problem. I can re-establish full engine power if I cut the ignition momentarily while rolling.

I have taken my T4 three times to my local VW garage but they cannot identify the problem. The last time they suggested that the only solution would be to replace the turbo -an expensive solution. However I'm not convinced it is solely a turbo problem as if turning on and off the ignition resolves the problem, temporarily, then surely it is electrical related.

Any ideas? Any one who has come across the same problem?"

RESPONSE:

"Hi guys, there is nothing wrong with your turbo's!
The problem is that sometimes the turbo's boost/output are ajusted just a little to high!
This means, that under perfect turbo conditions, the boost-peek will be just a little to high for your ECU'S. The ECU will switch to "limp-home" mode.
This Ecu will go back to normal mode after some minuts if the boost is not peeking! . You can also turn off and on the ignition to make the limp mode go away.

THE FIX:
If this is the problem on your car, VW will be able to reed all the limp-errors and delide them.
You can fix this by ajusting the axuator on the turbo, take away a little of the spring tension./boostpressure. it is very senitive, do one turn on the axuator at the time maximum!

If this is not your problem, tjeck the boostpressure regulator!"

http://www.volkswagenforum.com/forum...ead.php?t=3153

Roderick

Thanks for the response and the content. Have informed the garage where my car is parked and they will try the recommendations next week! Will post the outcome.