Power issues.
So i went out and started my 92 F150 and i noticed that when i put my lights on and the heater that all the lights would dim out then it would be fine for like 5 minutes then do it again. its almost like there is a serge somewhere. I put a new alternator and battery in it a couple of months ago. now this also happens when i take all the load off the system. ie. turning off all the lights and fans and just having the truck idle. so if anyone can somewhat understand what im saying any help would be awesome.
Thank you very much.
Jon


