okay im not sure if anyone else has this but here goes
my alternator is not charging when i drive pretty normal but it does start charging if i drive over 2500 rpms so im thinking the voltage regulator or just a very messed up alternator or maybe the last person to own this truck messed up the harness

any ideas?
i already asked the local auto store ad they told me to look if the belt was slipping... but i doubt that

 

Check the belt.

 

i did and its new but now i have a bigger problem, now ill turn the key to the on position and everything will work fine until i try to start it it will kill everything and ill have to take the battery out for 30 seconds to get the electrical system to restart i tried to jump the solenoid with a wrench and it did the same thing, 88 f150 4.9 auto if that helps i really have no idea

 

my 89 f150 did that too, it ended up just being the pos. battery cable

 

thanks ill check that

okay it seems like its the positive wire beause ill cross the solenoid and it will shut off and ill tap the positive wire and the electronics will come back on anyone have an extra positive to soenoid wire in my area...doubt it but i also cant beleive that there is that much resistance there

 

You might just have broken wires under the insulation or in the terminal end.

 

ive been working so i couldnt get back on here but theres a wire with a butt terminal covered in oil that i didnt see that keeps getting loose

just makes me wonder what else is crappily repaired like this

 

My buddy had a similar problem with his 40th aniversary edition mustang. He found a faulty ground and that fixed it. Geta voltage meter and start back tracking.