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Q: I have a 96 Isuzu trooper that while driving with the AC on, the voltage meter will jump all the way up, after about five minutes.

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I have a 96 Isuzu trooper that while driving with the AC on. After about five minutes, the voltage meter will jump all the way up, the engine is bogged down when trying to take off and when i put it in park the engine races up. When this started, I had the battery checked, it was bad so i replaced it. Today i replaced the AC belt. Still doing the same thing. If i drive without the ac then it runs fine.. Ive read it could be coils, O2 sensor, or alternator..please help

My car has 169000 miles.
My car has an automatic transmission.

Hi there. If the voltage is going all the way up, then it may be overcharging and can damage the battery and other components. Have the alternator tested to see if it is overcharging and replace it if it is. If you need help with having the diagnosed, have a professional from YourMechanic inspect the electrical system in order to have the correct repairs done.

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