Loss of Power, Limp Mode ??

[xlray]

A strange thing happened on the way home today. I used a bit more power than usual to overtake on an uphill dual carriageway stretch of road. Then the car (XL TDi 140 DSG) lost power. I had to switch into manual mode and change down (to 4th) to keep moving up the incline. On reaching the top I was able to change into auto and go down the other side of the hill, but the car would not change into 6th gear, and never fully warmed up.

I managed to exit the dual carriageway and on a side road turning off the engine and restarting restored normal power.

Now I was low on fuel, but the light had not come on, but is it likely that going up a hill and booting the car would cause a fuel starvation and a temporary switch to limp home mode.

After the re-start I continued to the garage and put in 47L of fuel, which is about where I normally fill up. At this point the trip was showing 100 miles remaining.

If it had gone into limp mode will this be permanently stored in the ECU.

I guess I need to update my VAG Com to find out!!

Any thoughts on this would be appreciated

xlray

[Mike5]

Various things can cause the ECU to drop into limp home mode. My previous 2004 Altea 140 BHP did it several times when working hard. The fault light would come on and it needed a restart to clear it. The diagnosis was the turbo control valve, which was changed under warranty. A few months later with the caravan on the back it did it again, then again. This time out of warranty. A few monhts further on the turbo failed due to carboned up variable vanes. I assume the original fault and not an uncommon one for all TDI turbo's. Expensive failure.

I am not saying this is your problem, but if under warranty make sure the turbo pressure is checked because even if carboned up the operating lever still moves if stuck in max boost. May give you something to go on.