I haven't been using my car for a few weeks as it has been nice weather and I have been force to ride my bike to work so my car has just been used to potter down the shops.
Since last taking the car for a good drive I have changed the Fuel filter (ebay purchase and cut the old one open and it was filthy), fitted oil catch take and simplifed the PCV system and finally made a heat shield for the cone filter.
Anyhow I went to take the car for a 'drive' on thursday and it is running like crap under boost, it feels like it is pulling back and spluttering.
So i decide to do some logging on vagcom and on channel 020 and the ECU is pulling 8 and 9s on the ignition advance at around 4500rpm under heavy accelleration in 4th gear. MAF flow seems good to this point but I backed out at anything above 4500rpm to save any damage to the engine.
If I accelerate in a gradual manner the car is smooth and revs to 6000rpm with no problems.
The MAF has been replaced and the problem is still there. All the hoses have been checked and they all seem fine.
I dont know if I have a fueling problem, if there is a problem with the ebay fuel filter and this is causing lean fueling hence the high ignition advance CFs. (is this the symtom are the cause??)
Any ideas or thing to try would be greatly be received.