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Q: Alternator glowing red hot. The engine don't rev up in drive, but revs up fine in park. Whats going on?

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drove home from work in traffic. smelt burning plastic or electrical when i got home. Checked under hood to see alternator glowing red hot. made mistake of driving with it... car lost engine power on the highway. pulled over put in park. i could rev engine in park however when i try to rev in engine in drive nothing happens . then battery died after leaving it in park engine running on side of road . 340 000 KMS

I'm assuming the alternator is toast.

My car has 340000 miles.
My car has an automatic transmission.

Hi there. What happened is the voltage regulator in the alternator failed. The battery died due to the alternator not putting the voltage back into the battery, but instead it cooked the battery with a higher voltage than the battery could handle. I recommend replacing the alternator and the battery.

If you need further assistance with the battery going dead, then seek out a professional, such as one from Your Mechanic, to help you.

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