[davidws6]

If it was fine before, probably the fan motor is starting to fail.

Is it the same if you rev up the engine a little? If you have a 15% or smaller underdrive pulley, that will make a big diff. @ Idle..

However, I would not rule out the alternator. I had 1 checked 2 times and the parts store tester said it was good. Stuck it back on the car and boom, 14 volts, just for a couple of seconds, then down to 11volts again. I stuck a used alt. off another car on, solid 14 volts.