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Car shaking after jumping a battery

I accidentally left my car on overnight and my battery was dead in the morning, of course. I got it jumped and I drove all the way to work, but every time I slowed down at a light or for traffic the car started shaking. It has to be fairly slow before it starts happening, say 15-10 mph or lower. It never did this before the battery went dead, and it stops as soon as I gave the car any amount of gas at all. I’m hoping this is just a temporary side-effect of having to jump the battery. Any ideas what the problem might be?

Sounds to me like your alternator can’t handle the load at low-RPM…and,with the battery low, it can’t pick up the slack.

It’s possible that the battery was damaged when it was “deep-cycled,” that the alternator was damaged trying to re-charge a dead battery, or both.

What I would do is go to a parts store and get my battery and alter.ator checked out. They often will do this for free! (Not because thy’re “nice guys” as much as they want to sell you a new battery/alternator.)

Hope this helps. If the car starts acting like this again, try shedding all the electrical load possible (radio, fan, lights) and see if it helps any.

What are the particulars on the car? Make, year, model, miles, color, leather seats, smoker/non smoker, etc?
You say you left your car on?? On how? Running? The key in but not running?

Come to think of it, if you left the key in the run position for a long time, it is conceivable that one of the coils in the coil pack has opened up, causing it to miss one cylinder and run like a hooptie…

It’s a 2001 Pontiac Grand Am. Apparently I didn’t turn the key all the way to the off position before taking it out last night. I assume that’s what caused the battery to die.

I double checked on my way home from work tonight. The shaking starts when the car gets under 10mph. Also, it stops when I switch the gear from drive to park.

i would start by having the battery put on a slow (10amp or less) charger for severaal hours and see if the battery comes back from the dead

I am in agreement with the first response, from “meanjoe”.

Your alternator is designed to keep a battery charged, but it is not really up to the task of recharging a dead battery. Whether the dead battery damaged the alternator, or whether an alternator that was already becoming weak was unable to keep the battery charged prior to this incident, I think that the current situation is the same, namely that you likely need to replace both the alternator and the battery.

However, I think that Big Marc’s approach–of doing a slow charge for several hours–is a good way to start. If that does not help, then the next step should be to get both the alternator and the battery tested at an auto parts retailer.

Edited to add:
In addition to resolving your battery and/or alternator problems, I think that you need to have a mechanic look at your ignition switch and/or lock cylinder. I am referring to your statement, “I didn’t turn the key all the way to the off position before taking it out last night”.

You should not be able to remove the key from the ignition of a modern car unless you have turned the key to the “off” position. If you have a defective ignition switch, the next problem that you will likely face is an engine that simply shuts off at random times while driving, and that is a real safety hazard.

Check for a vacuum leak. You may have pulled a hose loose.

Thanks for all the answers. Any idea of how much all this might cost? And how urgent is this? I mean, is this something I can put off for a while or do I need to get this taken care of right away?

Thanks again!

If your alternator is failing, bear in mind that they tend to go from failing to failed (dead) in a matter of…anywhere from a few hours to a few days. If you don’t want to wind up stranded and needing a tow, I would suggest that you attend to this situation very soon.

If funds are short, you can probably defer any possible work on the ignition switch and/or lock cylinder for…maybe a few weeks.