CarTalk.com Blogs Car Info Our Show Deals Mechanics Files Vehicle Donation

'01 Impala jerking irregularly

Two weeks ago starting jerking badly. Father said to check tranny fluid. It was low. Added more. A week later starting jerking again but not as severely as it did the week prior. Checked the fluid and it was fine. The next day didn’t jerk at all…it didn’t jerk at all until a week after that. I was out and about so before I left the parking lot I was in to go home, I shifted through all the gears on the column. Took off from the parking lot and the jerking stopped completely. Is my tranny slowly dying? No warning lights have come on yet (so is there a code to check?). Going to take it to a local transmission shop but wanted to get any other info I could.

Oh and the tranny was flushed about 20k miles ago. It currently has about 145k miles on it.

Perhaps you could tell folks all about the conditions under which it jerks. Perhaps while you’re sitting stopped at a light? Perhaps only when you accelerate? Perhaps only when you decelerate? Perhaps only when steady on the throttle? Perhaps only at certain speeds? Perhaps…you see where I’m going with that. “My car jerks” just doesn’t give anyone anything to go on.

Perhaps you could also fill us in about other things - like how old your plugs & wires are. Fuel & air filters?

The lack of a check engine light on that car is meaningless. Many of the transmissions in those things are troublesome and most of the important codes don’t turn on the check engine light. But they also won’t be read by a typical code reader either.

The tranny was flushed 20K ago. For the first time ever? Was the filter ever changed? After the service was done was the fluid checked and found to be at the right level? If it was and if you were recently low then you have a leak.