My 2000 ssei is acting funky. If you go up a hill, lef off the gas, then push the gas in again but only enough to maintain speed, the car seems to lurch. The tach is jumping up and down a bit, and the problem goes away if I push the accelerator down more.
You know, it'* funny to see this thread because I recently noticed the *exact* same behavior when going up hills trying to maintian speed. It'* very subtle and my tach jumps up and down very little, but it'* definitely there and it is occurring.
I have nothing constructive to add other than a "funny you should mention it".
This is a common 'mystery' problem with 3.8L, no known fix other than pushing it a little harder?
I often thought it had something to do with the transmission and vaccum but others have reported the same thing and no one has found a solution yet?
I felt it also on my Bonne I took it to the dealer, and they said it was corrosion on the coil packs the corrosion was on the spade connectors on the bottom, and the posts where the plug wires connect. So I replaced them (hence the high energy coils below) cleaned the connectors put some dielectric grease on, and no more jumping. At least it is a good place to start.
My problem has been fixed. Luckily I bought the extended warranty on my car. Ittook some research on their part too. They had to contact national tech assistance. It turns out that in my case it was the input shaft bearing on the transmission that was causing the tranny to jump out of gear. I think I got the part name correct.