topgun129

Hi All,

I went to start my car this morning and it wouldn't start. I jumped the battery from another car and it immediately started (like within a minute of connecting the cables). When I started to drive the car I noticed the cruise light in the dashboard was dimming a little and when the transmission was shifting the car jerked/hesitated for a moment.

I'm wondering is this a battery issue (it is old on my car and there is some corrosion on the terminals) or could it be the alternator?

After seeing all this I immediately drove the car back home. After turning it off I went to turn on the car again and it would not start.

BDSL

After boosting, remove the cables and let the engine idle. If the engine stalls after a few minutes, then your alternator is faulty.

Hayk

iTrader: (1)

Have the battery tested at AutoZone or a local car shop. They have a machine that can put a load on the battery and see how strong it is. They can also test the alternator, which is quite simple.

topgun129

i'm assuming to test the alternator i would have to remove it?

Hayk

iTrader: (1)

No, not at all. You can test its charging ability while the car is running. It should produce over 14 volts if it's able to charge the battery, if I recall correctly.

repairmatt

Yep, that is correct. Quick way to test if you have a DMM (digital multimeter): Set the meter to DC volts (or if it auto-selects between AC and DC just put it on the "volts" setting), put the red lead of the meter on the positive terminal of the battery and the black on the negative terminal. It should read about 13v at idle. Revving it pushes it up near 14v. If it doesn't do this when you rev it or the voltage stays near 12v and is falling as the car runs, you have a bad alternator. If you had a bad battery it would run okay and act normal as you drove around, but you would likely have to jump it every time you start it again.

pauloil

NEVER remove cables from batt. unless car is OFF. good way to fry alternator and cause other problems.

I agree with the last post: get a DVM. normal batt voltage is 12.4 to 12.6, 13.5 with alt. spinning.

285exp

I suspect he means the jumper cables, not the battery cables.

BDSL

Yes. Thanks for the clarification.
I used "the cable" because that was what the OP called it. I don't want to confuse him.

pauloil

thanks for the clarification. I think a car will also not run well and stall with a faulty battery. you can't charge a dead battery

BDSL

Yes, it can run with a dead battery.

DRACO A5OG

Autozone or AAA can isolate the issue, then you would need to remove the component to make certain, because according to Autozone, their analysis is only 90% accurate on the car, still not bad but it could be something else.

For me it was a suspected bad alternator but when I benched it was fine then I tracked it down to a bad connector. Saved bucks that way.

Get a DVM ( digital volt meter ) it will save you more than once and well worth it.