5 days ago, I went to the grocery store and when I came out the 2000 Jetta 1.9L TDI would not start and would crank like with a weak battery. I walked home about 10 minutes came back and jumped it. The next morning it started and I drove to buy a new battery. It started again I went home and installed the new battery. Since then I've probably started it about 12 times. So then this morning, I start it, drive somewhere, it sits for 10 minutes and then it has the same weak battery syndrome. I cranked it and cranked hoping it would turn over. I opened the hood and there was smoke coming from the starter solenoid connection area with a flame. I blew out the flame. I tried to jump start it. No success, just more smoke. I felt the positive battery cable leading to the starter and it was very hot. I assume I need a new starter. A guy at work says it could be that the alternator is overcharging. What should I do???