I got the 3.5 swap in my 4th Gen., 00VI, with Stock '97 ECU. I've been driving quite hard these past 3 days. I came to a stop earlier this evening, and the car was bucking, not hard bucking, but it was bucking like there was a misfire. There were absolutely no codes, and the RPMS were VERY steady. When I would barely step on the brake, so much so that the car was barely moving, I would feel it buck a lot more. It would just vibrate back and forth and it was felt throughout the whole car. This happened for atleast 15-20 minutes. Then out of the blue when I pulled in my driveway, IT STOPPED BUCKING! I had the car stopped in gear, and it was smooth! I was like WTF?? I opened the hood looking for anything out of the norm, and all I could hear was the WRRR from the VI it's always been there. I had the car in gear with the e-brake up and looked for anything weird and still couldn't see anything. What can this possibly be?

 

Just to be nitpicking How did you have the car in gear & ebrake on & look under the hood without it stalling

 

Auto Tranny ... 10 char....