Sorry to here this, I had the same problem a while back and found out there were to many ohms going to the coil, ie no resistance in the line. Your coil operate's at a certain amount of current and if it gets to much it heats up.
Some of the Pantera's have/had a resistor wire or balast resistor rated at approx 1.4 ohms, hard to say what has been done to the car over the years. I obtained mine from summit, has worked flawless since.
Mark
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