I got a buddy who bought a used 91 grand prix. Been having nothing but problems. Just had a new motor put in. at his cost. The plastic upper intake melted, dropped parts in the intake, stopped a valve and the rest followed when the piston came up and out! I know these engines (3.8) had problems with the intakes. I did a couple when I was a GM tech. Just want to know if there were any T.S.B's or programs on this problem.