Engine Problems/Issues

[smass]

My Mk4 Golf GTI 20V turbo is having major engine issues at the moment, some mornings i can start the car no problems other times the car will hang at 500rpm and shake like it wants to conk out,when putting my foot on the accelerator nothing will happen at all, if i power the car off then on sometimes it will clear up or remain the same. I have had the car in a VW approved garage and a diag check showing a pressure drop between turbo and throttle plate, they replaced the turbo pressure sensor,checked induction system and cleared code. The management light has gone but I still get the same problems, also had the air flow meter replaced a week before this.

sorry for the long story, but i need to get this sorted, if anyones had the same issues or know of what could be the real problem with the car, I would appreciate your help.

thanks