Chrysler Repair: Alternator voltage control problem causes miss, voltage fluctuation, plymouth voyager

Question
I have a 1993 Plymouth Voyager with 3.3 engine. It has an intermittent miss or cutting out. It has never failed to get me there. Early on when this first started, I noticed if I raced the engine it would run OK for awhile. It got worse. The check engine light would come on when this miss started. It was code 41. Mechanics couldn't figure it out. They couldn't understand why a code 41 would cause it to miss. Finally one noticed by monitoring the voltage while driving it that the voltage would go up when it started the miss. By turning on the lights and heater fan it would pull the voltage down and it would stop missing. One guy added an external voltage regulator on it but it still misses and the check engine light stays on all time. It seems worse in the morning when it's cold. If it starts doing it while running with the lights and heater fan on, I can push it into neutral and rev the engine and it will start running ok again. One mechanic said he had read about the cam position sensor causing a voltage fluctuation. Have you any thoughts about the problem?

Answer
Hi Garry,
If the voltage control of the alternator is not keeping the voltage within normal range, then I would suspect that the dark green wire from the alternator to pin 20 of the powertrain controller 60-way plug has an intermittent short or the controller is failing to do its job of oscillating the grounding of that wire so as to produce the desired output voltage or the alternator itself has an intermittent internal ground of the field coil wire. I would try removing the 60-way plug and the wire at the alternator and see whether it is grounded; also try shaking the harness to see if you can make it ground. If that "passes" then I would carry along an ohmmeter and the next time this happens stop and check whether the post of the alternator to which the wire is attached is grounded (after removing the wire) to check if there is an internal grounding in the alternator that is happening when it gets hot. If it passes that, and when you hook it up again it still is over- voltage, then I would suspect that the controller is failing in its function to control the grounding. Most likely the field coil is grounding itself when it warms up, which causes the output voltage to go to the max, but you can't be sure unless you do these checks. Of course you can replace the alternator, on a hunch, but that is not the way I advise you to get to the bottom of the problem with the least cost/frustration.
Those are my best ideas.
Roland