I have a Chevy Venture 2001. From the time I got it,,,,I found out that the battery was moving AROUND and going into the drive belt and sparking. Check for a loose battery as there is no way to keep it from moving around. I used Cable ties any way I could to stop it from moving. Also,,,the negative cable is too close to the drive line so Cover it by cutting a big piece of Rubber hose and clamping it over the cable with cable ties somehow to keep it from moving also.
If you can secure the battery from moving,,,,it might solve some of your other problems,,,try it and watch. Good luck!
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