Hi everybody I have a 89' Aerostar 3.0,2wd,at, power everything and was wondering if anyone could help me with the following problem, When I bought this van in 98' it had a bad alternator so I replaced it and everything was fine, after about 10 months my battery went dead and replaced it and the alternator again!!, so on and off since then I've replaced the alternator about 5 times. during that time I've noticed my headlights/interior lights etc. dimming, and the battery meter (electronic dash/gauges) going down when I let go the gas pedal and while in idle, Even more so if I turn the A.C or Heater on( it goes up when I depress the gas pedal). I do not belive this is normal as I have checked other vans and they don't do that. So far I've replaced the following:
Battery (twice) ,Alternator (5 times!!), Alternator conectors, Both black and red battery cables and starter relay.
Could it be that when I replaced the alternator the second time they gave me one with less amps? or my idle is to low??(it's on the 3rd bar/or around 700 rpm) is it a bad fuse link? Please I need help!!!

HL.

 

I would check your idle speed like you suggested. It's controlled by the computer, but you may need to take your throttle body apart and clean it up. Also clean up the idle air bypass solenoid mounted on the throttle body. A little bit of dimming will be normal with a high electrical load.

 

Is there an internal regulator, or external, if it is external, i would get a new regulator.

 

The alternator has an internal regulator, and I've had it tested so many times that I can't remember anymore. Could it be a ground issue? There is a ground wire comming off the battery smaller that the main that has an inline connector that looks like a fuse holder but is not and the wire is not in that great a shape or I shorted something, as I seem to recall that the issues started right after my second alternator and first battery went south on me and had to give it a jump. Thanks for your help.