Tdi going into limp mode after re-con turbo UPDATE...

I know some of you have helped me here http://www.myturbodiesel.com/forum/f5/tdi-going-into-limp-mode-after-re-con-turbo-3408/#post16220
The best I have managed to do is adjust the turbo actuator stop screw as it was a little on the long side.. have yet to adjust the VNT adjuster tho.

Anyway, I was bored so I though I'd refit the cheapy aftermarket tuning box I've had sitting around (which goes between the ECU & the injector) - all I can say is that it feels like a new car.

It pulls from 1200rpm like it never used to & (because of the stop?) there's not as much lag & it pulls much better through the gears. Doesn't look like there's much in the way of smoke & the MPG has gone from 29 to 43 on a 40min motorway drive Surprise

Best of all, it hasn't gone into limp mode with the -'ve deviation code (or any other for that matter).

AFAIK, these tuning boxes convince the ECU to overfuel. The question I have is why my Tdi wasn't doing the correct fuelling in the 1st place?

Was my ECU knackered or has it been 'adapted' by previous use of this tuning box?



I can't work out why this seems to have solved the problem when the car should be like it without this tuning box.


Can anyone shed any light on this?


Cheers,


Nic