I had the same issues with mine, it started when I changed out my belts.. anyway, I tested the battery, it was good, test the alt, it was good, checks the grounds I could get to, and it was good, added some more grounds, still had the problem, decided i was tired of messing with it so I replaced the alt, did not fix it, replaced the battery, did not fix it either, i bought the a new wire harness, went to put it on, noticed that the bolts on the solenoid were less then finger tight... ooops... I assumed that it was fine down there, you know what i mean? so i replaced the wire anyway, and it fixed my problem, now I am not sure if it was the wire (which was beat the hell out of) or if it was the loose bolts, I'd say both.... so I'd double check all the connecting points, all the hold downs, and work from there