I need some electrical advice Please

[G.R.]

I believe all one wire alternators do but if you have a regulator then your alt must be a 3-wire. There is a possibility that the Motorcraft regulator is faulty. Disconnect it(after removing the battery leads) remove it and take it to your local Auto Zone, Checker or parts house that does free electrical testing.
The car does start though, all electrics work? Any other gauges irratic or not functioning properly? Battery is not being drained?

[Velox]

JB the stock SPF has the Ford regulator mounted up under the left front fender, and the stock system would not have a one-wire alternator. If you in fact do have a one-wire system, then the stock regulator has been disconnected and perhaps just left there for whatever or future use with redo of a stock setup. I converted mine to a one-wire alt, and removed all the old wiring and Ford regulator. If you have a one-wire alternator, it would be obvious, because it has... one wire on it, not the usual harness connector. The SPF also (stock) ships with an ammeter, not a voltmeter. I have converted mine to a Smiths voltmeter, is that what you have in your dash? If so, it reads up to 17V. If you pegged that, your system was putting out 18V or more, highly unlikely, but meters do go bad. I would think you need to check the actual voltage with a good digital meter at the alternator post when the engine is running and your gauge is pegged, that will tell you for sure what the system actually is at. If really that high, your one-wire alternator's internal regulator would seem to be toast. If reads normal (13 or 14V or so) running, then your voltmeter is the problem - lose wires, ground, whatever. If you really have an ammeter, and THAT is pegged, that is an entirely different problem, flowing that much current through the system big trouble, just my thoughts FWIW

[RICK LAKE]

JBCOBRA JB you belt is loose or you but some sealer on it like a belt dresing. It is causing the belt to slip and grip. When it grips the gauge pins, the regulator stops charging and the gauge drops to protect the system. And goes back and forth. Try getting some fine sand paper and sand the inside of the pulleys where the belt rides, alt too. Then clean these places off with brakekleen. I would get a new belt because you cann't get the silicone or wax off the belt and out of the pours of the rubber. Try this. If the gauge is still pinning you have either a loose connection to the battery or you have wetted the Alt and possible damaged the internals. I would say with out seeing it you cleaned the car too good. Rick L.