HELP- CAR WONT START

[jimdrechsler]

I own an 89 mustang convt. I turn the key and the battery light and oil light come on, but when I turn to start it, I hear one click and then nothing. When take the key out and put it back in to start, no interior lights come on at all. It does start with jumper cables, but when it is running, I can hear strange sounds (radio is a little distorted, the buzzer noise that the key is in the ignition is distorted too) after I turn the car off again, it will not start up and the same thing happens. A few weeks ago while I was driving about 65 or so, the RPM's jumped up and down real quick. When I pulled in the driveway, the car died and there was no power till I jumped it. The car started fine fine for about two more weeks, now it wont start at all without a jump. I tested the battery and the alternator, and they are both good. Any ideas!!!!! Thanks
Jim

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