On my 97 Ram 5.9 gasburner, the motor developed a miss under load. Changed out the orginal 165000 mile distribuator cap and rotor button, with an autozone cap and button. Truck ran great for a week, then started missing again. Pulled cap off, the center button was completely burned off. Put new one on Tuesday, truck ran great for about 6 miles, then started missing again. Any thoughts?