Have a friend with a stock but aged 88 GTA Notchback about 100k mi. He doesn't know I'm posting but his problem has me intrigued.

Once the engine has been running for a bit one terminal will get so hot it will burn you. This is not from engine heat, it is some kind of electrical problem generating the heat.

I can't remember if he said it was the + or the - side, I have to ask him. The car does not otherwise drain the battery or have other weird behavior.

If anyone has any clues as to what this might be or how to troubleshoot please comment. I can easily find out if it's + or - if I can get some ideas to help him sort it out.

I suppose the first question is does it happen with key on engine off. It sounds like there is a ground but why would the terminal heat up? And no blown fuses or melted links...

Cheers, Tim

 

Troubleshooting would be done with a multimeter. I'd start with battery voltage, see if it's overcharging. Clean all grounds, that never hurts. If they're the original side post battery cables, they can corrode internally and appear fine on the outside. The cables on my '99 were turquoise with corrosion for a full inch behind the ring on the end. Makes it hard for the juice to flow, energy gets turned to heat.

 

That's usually from bad/dirty grounds and bad contacts/connections, and primary cables (both positive and negative,) that have/are degrading from within.
Peel back some of the sheath and inspect them, or just replace them.

After you've completed that task, check alternator output.

 

The terminal in question is loose and/or corroded.

 

Yes, loose connections cause heat.