weird electrical problems

[79'293stang]

ok guys heres the problem, on occasion out of nowhere my cars battery will go dead for no reason and the car wont charge for crap and everything will dim out and it will start to back fire due to lack of charge but then teh next day without doing anything to it it will be just fine it seems to do this every 3 weeks or so out of nowhere, any ideas?

 

[roush 97]

I'd look into the alternator. Have it checked. Could be working part of the time. Also could be the voltage regulator. May even be a wire going to the alternator that is broke. Had that trouble on an '83 f 150 one time. Sometimes it would charge and other times it wouldn't. It wasn't broke completely so it wasn't noticable till I got the voltmeter out and went to checking wires.

 

[79'293stang]

thanks i'll make sure to check it out