passat tdi limp mode no cel

[audi-a6]

hey all, sorry not been on for a while, sadly had to let the a6 go and went back to a skyline. However i have just bought a passat 1.9 b5.5 tdi 130 as a run around..

I bought it cheap as it had a blown turbo, so bought a new cartridge for it, took the turbo off and fitted new cartridge, while i had the turbo apart i cleaned the vnt nozzels as they were pretty coked up. Also cleaned inlet and egr valve. Put back together last night and took for a drive and drove almost perfect, had a bit of smoke (probs still oil in the intercooler from old turbo) and also a slight engine judder/hesitation above 3k..... other than that she was fine.....

...... until today, it will not rev past 2.5k, it like its hit a rev limiter so i presume is a form of limp mode :-/ I got no CEL light and no codes stored in the ecu..... but also i noticed the the cel does not come on even for a second when first switching ignition on, so i unplugged maf... still no cel. drove car and problem still there, this time with less boost so guess the maf is fine, but if the maf is unplugged, shouldn't it throw a code?

some light on this would be apreciated

 

[davc]

If you switch the engine off then back on, does it drive ok until you hit 2.5k again?

If it does it could be over boosting. The vnt mech may be the seizing, although I reckon your maf is the culprit. I had the same issue a few years back on my golf where it wouldn't rev past 3k.

When my turbo eventually went, it would go into limp mode at 2.5k.

Not sure about getting faults with the maf unplugged, but I know from experience that when they fail you don't get any codes.