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1996 Ford Taurus - recurrent alternator light

Alternater light comes on. I take battery cable off for about 15 second light goes out for sometimes weeks. Now the engine surges at higher RPM and sometimes fells like it is miss firing when I first start it in the morning. It is housed in my heated garage. I have repaplace the coil pack about 2000 miles back,which was cracked. Please help and Thanks

Have you had the battery/charging system tested?

Tester

I replaced new alternater about 5 weeks ago when the light came on. Now it’s back on

Did you get the battery checked?

I replaced the battery 2 years ago with Interstate 6 year. Car starts fine and light goes out after I removed the battery cable for 20 seconds. It maybe weeks before the light comes back on. Also after the light comes on and I remove the cable the engine seems to mis in the mornings for about 2-3 miles then runs fine the rest of the day. Thanks for your help.

AND

Right now you are just guessing things are OK based on a 2 year old battery and a 5 week replacement alternator. The current condition (pun intended) is totally unknown so until you answer these questions, anything we might add as help are just wild donkey guesses.

You aren’t removing the battery cable with the engine running, are you? That can fry electronics.

Check both ends of the battery cables, as well as the cables themselves. Also look for any smaller grounding wires and verify they are intact.

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Thanks for all your help. I am a 40 yr mechanic but this one has me stumped. I removed cable when eng. off. I have put a load test on battery and it’s fine. Today everything is working fine. Alt.lights out and running fine. Do you think I have two problems,one electrical. the other fuel?

@Richard09 :
Have you checked the battery and/or charging system?

I replaced the battery and had the alternator checked. The volts when first starts is 12.8 it takes about 15 second for it to get 14.3. When I took it for a drive it still had a slight miss but the further I drove the better it got. Is there a reason for this miss due to the slow volt gain? Thanks

The miss may be from your removal of the battery cables which causes the PCM to revert to default values.

Do you think it will get better the more I drive it? Thanks

Check voltage regulator, should immediately be producing easily 13-14v.
Check clean the MAF

Forgive me what is the MAF?

I forgot that’s mass air flow. at my age it’s easy to forget.

The misfire should resolve if you stop disconnecting the battery.