PLEASE Help!! charging issues...91 GT

[scorpionSStang]

well at stop lights or idle the headlights are dim and if any accesory is on the go that much dimmer unless you rev it up. even after the undercrive pulley has been removed. the problem has slowly gotten worse over about 2 years.. after dropping the steering cloumn down to install a speedo cable. the charging gauge reads almost in the red. a powermster one wire style 140 amp altenator, a new battery and a performance grounding kit hasnt helped any either. off and on the cruise control and horn would quit working then start again..now it just blows the hell out of fuses each time you try to put in another one. the dimmer switch has also been replaced as it starting acting up. it will drain a battery in about 2 days or so and if you try to start it with the battery low you can turn the key off take it out and the motor will still try to crank over!! a new solenoid and starter didnt fix that either.the door chime and air bag light have came on also a few times for no reason too??. the past couple times i have driven it the car shuts down after about a half hour of driving..u have to wait about 10min before it starts again..i have tried my best to check all the wires around the steering column and cant find anything. i have used a ammeter to see if there is power being drwan when the car isnt running each fuse at a time. using an ohm meter you can stick one end where there horn/cruise fuse goes and read continuity on any metal object of the car. ive read that there have been issues with the altenator harness(though its not hooked up) and the ignition control modules...havent replaced them though... please help if im over looking anything or if i just need to go over all those wires again....thanks again for your time.....

[dana]

if your blowing fuses you have a direct short somewhere. You might want to get another harness if all else fails.

[Joel5.0]

Recommend going back to the basic stuff first:

- Main battery ground to block cable
- Ground strap from block to firewall (double it if it wasn't part of the performance grounding kit)
- Make sure ground connections are paintless, clean and that a star washer is used
- Battery (+) cable and terminal connection
- Power distribution fuse links @starter solenoid or connection @distribution box.
- A voltage output check comparison engine idling measured at battery and alternator output post....difference is greater than .4vdc?...have a connection or wiring problem or, output wire alt to battery needs to go thicker.
and last but not least, make sure the ignition switch assy. is not due for replacement.....it goes bad and it starts doing a lot of the symptoms you are having in the car.
My 2¢.

[RdRunnr]

What condition are your battery cables in? Are the clean of corosion around the terminal ends? Is the ground wire good on both the terminal end and the end that is attached to the timing cover? Have you thought of changing to a 130a instead of the powermaster? They don't charge well in my experiences with them.

[Bane-]

foxes have shitty alt's in general but I am not familier with the powermaster ones, if ya have a local pick an pull junkyard try to find one of the 3g alts. That way its around 130amp and its a ford part so everything is already compatable, think you have to run 1 extra wire for it though. Tbird would have to come in on what models came with them. I know my 00 ranger has one and I think the taures' had them but I dont remember the years.

[Zim]

for your cruisecontrol problem... I was blowing that fuse too and it turned out it was happening whenever id turn my a/c on. The clutch assembly on the a/c compressor went bad and was shorting everything out so i unhooked it and all was fine. Theres defanitely a short somewhere... just get a bunch of fuses and keep blowin them and unhooking different accessories till you find the culprit.

[scorpionSStang]

at first the fuse would blow no matter if the car was on or off...i pulled the harness off the a/c clutch and stuck a fuse in and i did not blow..but when i started the car it blew...oh well i only had a few minutes to mess with it anyway...my door chime fades in and out now,...most of the time u can barely hear it...thanks for your and all replies

[MonteCitan]

I almost think the door chime is unrelated... my '89s was completely dead and my 92s is very faint..

Follow the AC harness.. since that seemed to help when you disconnected it.. Follow the harness as far back as you can.. look at all corners and edges to see if its chafed through somewhere's, it could be that connected, the ground side or w/e of the AC circuit was constantly shorted, while the powerside was intermittently shorted to ground in the same location, with the engine running, the wires are vibrating around, and it could have contaced ground again..

as for the headlights dimming.. check voltage across the battery terminals with the headlights on and other loads at idle.. it should read between 13.9 and 15.0 volts if its not reading that, either the alternator is bad, the wiring has issues, you have a short somewhere's, a bad/loose ground (or check the wire to the starter solenoid.. I've had issues with that wire in each of my 5.0s..) or your voltage regulator is skewed..

let me know if you come up with anything.. I'm curious now myself..

[Zim]

I have a really low charge at idle (around 10-11 volts on the dummy guage) but I always attributed it to having the cam that surges at idle and having lights on etc. Ive wondered about my alternator too though because when I first start the car, it charges real nice and doesnt get bad at idle, however after the car warms up is when my charging issues start. It never gets to the point where it dies off though.

[Tbird232ci]

Cam doesnt have anything to do with charging. You alternator is always supposed to put at at least 14.4 volts as long as the car is running. My turbo coupe, having more electronics on it than you could imagine, never drops below 14 volts, even when the car idles low with all the accessories turned on. Im running a 130amp alternator out of a 96 Sable, which is similar, if not the same as the SN95's.

Sounds like a bad ground or something similar, go through and clean up all the grounds you can get to. Its free, and it cant hurt.

[Bane-]

didnt the 94+ mustangs get them aswell? or maybe 96..cant remember, just go into a parts store and ask for a 96 v6 alternator. and takes yours with you as a core.

[MonteCitan]

94+ got the better alternators..