Hi all,

2006 Audi A4 2.0 TDi 170 S-Line, 75k miles - Full Audi service history, ecu software up-to-date, not applicable for injector or loom recall.

An ongoing issue that seems to be getting slowly worse. The car used to stutter or surge, as in violently shake the car for a split second if cruising at low speed around 1500-2500rpm. It usually coincides with the outside air temperature being about 14 degrees C - the car showed no faults on VAGCOM.

More recently I've started to get a problem where the car seems to be holding back on power. Usually there's a good rush of solid power when you accelerate but its started to become hesitant, like the turbo isn't even spooling! I've tried a lower gear and given it the revs and it will surge back to power and accelerate properly. It feels almost like an intermittent switch of power on and off repeatedly. I do a lot of long journeys in the car and sometimes after a few hours of driving the engine light will come on showing:

000665 - Boost Pressure Regulation: Control Range Not Reached
P0299 - 006 - Short to plus - intermittent

001137 - Exhaust Pressure Sensor 1 (G450): Implausible Signal
P0471 - 006 - Short to plus - intermittent

I drove the car this afternoon to work and the whole journey felt like I had no turbo at all! Tried the lower gear trick I did last time and it felt like I've only got half power. What isn't helping is the rocker cover gasket is blowing AGAIN (I've replaced it with a genuine audi part 4 times this year) and dumping oil all over the EGR and DPF making a horrid oil burning smell. What I will mention is that the whole thing seems to be intermittent in itself. Some days it will act totally normal, then there will be days like today when its an absolute pig! A month ago I stripped the inlet system right down and poured a bit of oil out of the intercoolers and cleared up all the pipework, inlet manifold, EGR and turbo has no lateral movement.

Any help or advice would be greatly appreciated!

Regards,
Steve