So i read through the threads and the FAQ's to try and find an answer to my question. i have a 1987 s4 t2 and i have the dreaded 3800 rpm hesitation. i noticed this issue after a night of driving. first thought was blown engine. car runs great up to 3800, but once turbo should start to spool the car bogs and seems to have no power. the stock boost gauge shows that the turbo is making pressure. strange enough, sometimes it will spool and other times it wont. also after 3800 the car is seeming to pop alot. FAQ's say check all grounds, which i did. I replaced one ground wire and even added a grounding kit. i have also cleaned my fuel injectors which i have read can be another problem. if anyone has any ideas, or has had a similar problem i would love to hear what you did to fix it, thanks a million

 

Install a wideband O2 kit (or take it to a dyno) to get a good idea of how rich or lean you're running around the area of hesitation. Perhaps you have a faulty sensor and the ECU isn't adding the correct amount of fuel.

 

it was the alternator
thanks guys!!!

 

o.O

 

Glad to see you found the problem.