Hi I have had my audi for 12 months/ 10000 miles now and I have not been able to get to the bottom of the problem.
The car will only rev to around 3000 rpm in gears, top speed of 75mph, it will rev to 4000rpm in neutral.
Starts fine when cold, can take a few more seconds to start when hot, all glow plugs are broken!
Air fiter has been changed
New MAF (bosch) fitted (although this does show signs of being faulty but performed the same as the old one)
EGR blanked off
All pipe work checked for leaks, splits.
VNT mechanism is very loose and not sticking
VNT actuator seems to go up and down ok
1 error code on Vag com - 00550 start of injection regulation - control limit surpassed - intermittant.
No smoke but if i rev it to 4000rpm in neutral it will puff out a cloud of black soot.
Cam belt was changed by previous owner but i dont think he would have checked the pump timing, I only have free VAG COM so can't check it either.
Does this fault sound like pump timing if so how is it adjusted?
Thanks in advance