URGENT: Can a Blacksmoke uprated ECU fail and cause boost problems/limpmode

[alpenweiss2]

Hello

Our 1999 Passat Wagon 1.9 tdi 110BHP AFN has been running an uprated Blacksmoke ECU for well over a year now with no problems until recently. The car is with a British run VW specialist here in France where we live. They have had the car a few weeks and have had to replace the turbo and also a split boost pipe. They rang me today to say after fitting the new turbo and boost pipe the car is still going into limp mode but with no fault codes?

They have asked me to post them (they are 114 km away!) the original ECU from the car as they suspect the uprated Blacksmoke ECU is causing the issue with limpmode?

As I say we have had the uprated ECU (Approx 140BHP) on the car for many months with no issues whatsoever. Do you think it is possible that the ecu could cause problems?

I will be pretty fed up if they have to remove it and fit the original ECU just to solve the problem as we will lose performance and better fuel economy. Any thoughts?