QuestionI have an '88 Olds Cutlass with the 2.8 v6. After slowing down to say 15 or 20mph, and then giving gas to accelerate, it shifts down to second gear,( kicks down), with an almighty thump - as tho' the torque convertor was still locked up. Otherwise the transmission operates perfectly. I should mention that it has been rebuilt four times in 120,000 miles, even tho' it's driven very gently. Thank you.
AnswerHey Norm....how 'bout that Buick
Sounds to me more like it's the Throttle valve. This valve is what controls the shifting when you give it gas on the highway too, to go to passing gear. Even though it may work great on the highway, it could still be shifting too late or not at all when you brake.
I also did a bit of extra research on the subject with a friend of mine at the shop. We have determined that it could be the torque converter as well, but not in the way you think. I've noticed a lot of cars in my day that shift too late or not at all, and it was because the ground connection on the torque converter was corroded and it was not making a good connection.
Let me know if you need more info or if this works or not.
