About 2 months ago i replaced the battery and alternator. just the other day while driveing home from work i notice when i accelerate the volt gage drops and the battery light (AMP) comes on. when i level out and maintain a steady speed sometimes the light goes out and the volts read normal. they also read normal when at a idle. the belt was worn so i repaced it with no luck. I drove up to advance auto (where i bought the alt.) they tested it on the truck and said it and the battery was fine...

Any sugestions?????

I AM STUMPED!!!

btw this is on my 92 f150 XLT 5.0L

 

You have a defective alternator.
There should be some kind of warranty on it.

 

i took the alternator off this time and had them test it again. this time it failed.... they replaced no questions....

i still want to know why it pass on the truck and failed off the truck????

oh atleast it is fixed.

 

The in-circuit test is not as comprehensive as the out-of-circuit test.

Steve