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Automatic jerking while shifting

My alternator recently died and I took my car to a shop to have it replaced. Since receiving the car back, I’ve noticed that the car seems to jerk at random while shifting. It seems to happen most when shifting from 1st to 2nd. This problem didn’t exist before I had my car maintenanced. Any chance this is related to the work done and is something easily fixed or is it just coincidental timing?

Maybe it’s based on miles? Your car might be entering the zone of advanced part failure. How many miles? Ever have trans serviced?

How long have you had the car returned? I think the technician has to disconnect the battery to replace the alternator. Just as after you shut off your computer, the RAM is cleared. The computer now has to be reacquainted with the propulsions’ mechanical characteristics and probably your driving style as well.

@zing21, have you checked to make sure all the proper wires were correctly reconnected to the new alternator?

It’s at 120k miles. Trans has never been serviced. I checked the trans fluid and it seemed okay. Talked to my father (the previous owner) and he doesn’t think the trans fluid has ever been changed so I may try that.

About the disconnected battery, I had first replaced the battery myself before having the alternator replaced. I drove it a good 40 miles before that battery died too and didn’t experience this jerking. I got the car back on Monday afternoon.

I haven’t checked the wires. I can’t check that very easily just by opening the hood. I’m a college student and don’t have access to many tools which is why I paid the premium to have someone else replace my alternator.

What does your owner’s manual require for maintenance on the transmission?

You are way overdue for a tranny service. I wouldn’t recommend a tranny flush, just a new filter and fluid. The new filter and fluid may clear up the problem.
Get that done and have the mechanic check near the alternator. Many times while working in these tight spaces a mechanic will not realize that he knocked a vacuum line or wire off somewhere.


Year/make/model? Some newer transmissions require a memory relearn or resetting after power loss. It’s hard to give advice when the car is unknown.

Is there a chain that would be good to take the car to for tranny maintenance - It’s a 2004 Hyundai Elantra, by the way - or should I take it to a local mechanic?

Start saving for a new tranny.