The other day I was fiddling with the boost on my '86 TC... And now the car just won't idle quite right. It jumps around anywhere from 1900-2100 rpm's, which wouldn't be a huge deal except it is really abrupt in it's changes. Basically it jerks around in that area. In addition, when keeping a constant speed, the car kind of sputters. The engine jumps around a little. Any ideas? It's a 5-speed car.
turn the boost back to stock and slowly rise it with test drives inbetween or you may have bend, broke or cracks a vaccum line or boost line.