I bought the vehicle with a hard shifting problem i was told by a mechanic it was a minor issue and wouldn't be that much of an issue it was common but i had it down to i could shut of the car for 3 min or so and then i would be ok for a while usually till the next traffic light final result i had power loss i didn't think much of it until around 45 it would take about 4 seconds to shift long story short i wont travel far its not a complete failure but not far from it i don't blame gm or my mechanic there are issues with all cars don't hate the car or the company have it fixed and enjoy

I guess this is a real common problem with the Buick Century. From what I understand, the solenoid that controls when the car shifts shorts out, making it shift hard from time to time. You'll also notice a whining noise in the engine. If you shut the car off, and restart it, you should be good to go. For awhile. Towards the end of last spring, just about any trip at all resulted in rough shifting and engine whining. This is really a part that should last the life of the vehicle.

When we took it to the shop, we confirmed what we had already found on on the net. These Buicks go through shifting solenoids like water. I guess they start going around 20k. Ours has been fixed for over a year and we've put over 20k on the car, and sure enough it's already done it once (granted, this was on a rather long trip across the state of PA and it hasn't done it again since), however, we know that it's not going to go away.

If it isn't one thing, it's another.