1982 coupe.
OK guys what should I look for. The voltage meter and the GEN light come on while driving, The light goes from dim to bright and flashes and back to dim as the RPM's go up and down with the engine speed. The volt meter does the same it reads around 15 to 16 volts and goes up with engine RPM. The voltage with a VOM is 12 to 13 volts with the engine running, the alternator shows to be working as it should, it gives a constant 14 volts at all engine speeds an alternator check shows the unit to be working correctly. everything thing else is working as it should. is the gage bad? then why is the GEN light coming on, could the voltage regulator be bad?

 

Try measuring the alternator output w/ the battery disconnected.

 

OK Guys it was the voltage regulator. Got the part today and it work like a champ. Thanks for all the help.

 

Thanks for reporting back. Glad you got it fixed.