i have a 2000 a4 1.8t with a boost controler, for the past couple of months i had to take it to the shop cause it wont stay on.... first they told me it was the fuel pump...changed it. went a week driving well than the problem came back. then they told me it was the down pipe fixed it...ran well for another week and then it got so bad i had to tow it. the comp. is not reading any error codes. what could the problem be cause i dont want to be paying crazy amount of money and still have the same problem. Can some one please help me or if u have the same problem and solved it let me know

 

First thing, take out the boost controller and see if it runs stock. If so, the problem is related to the boost controller. Do you have a boost gauge? How high are you boosting?