I have a 1981 Mercury Grand Marquis and it keeps loosing power after 20 minutes of riding. I have anew battery and alternator. I unhooked the radio, AC compressor, and fog lights. It still dies.
I have a 1981 Merc Grand. The previous owner put a 5.0/302 motor in it. There
are a few things that has been converted on the car such as the fuel filter now
requires a 1976 filter. The factory recommended alternator is no longer the one
that works for the car. What could the problem be?