I would leave the jumper wire in (at the voltage reg) to give the field MAX current and thus full possible output of the ALT on the way to work in the AM. Also leave in the volt meter hooked up to the fuse box and watch the voltage to be sure it doesnt get to high, 15v,.. you can also see if it is getting to low, 11 v, and then lower current draw, turn the fan off ect to try to raise the battery voltage. The car will quit running at around 8 volts or so.

Tomorrow have your ALT and voltage reg tested at an auto parts store, something is not right.

Jim

 

i'll drink to that...

 

the 10.00 ignition switch is bad ford recall on these cars will confirm

 

drove the car to work this morning on a fully charged battery (had the charger hooked up through the night). didn't need headlights, used the heater sparingly. popped the hood before leaving for home to check the voltage. noticed corrosion on the negative battery cable. ran to walmart, picked up a new battery cable and a digital multimeter. i hooked up a jumper cable as a temporary ground in case the ground was indeed bad. started the car and observed the volts across the terminal. regardless of whether or not i had the jumper on the voltage was slowly rising (about .03 volts/minute). with the lights and the heater on the voltage was dropping quickly at idle (didn't remember to record the rate). drove home with lights and heater on and didn't lose power tonight, which i found odd. when i got home i turned off the lights and heater and checked the voltage. it was about 12.1, about .5 volts lower than when i had left walmart. with the lights and heater off it was still slowly charging the battery, but when i turned them off again same story of killing the battery. this is still not an acceptable charge rate.

since its not giving full voltage across the terminals with the lights off i don't think the problem lies in a draw stemming from an accessory. similarly, the alternator is putting out some level of current; or the alternator is putting out full current and something is using it all.

i'm really getting frustrated. my car doesn't like me right now. today the steering wheel even bit me (tiny piece of plastic trim was snapped and i bled all over...). i just don't have the heart to put her down. she just needs me to get her "spark" back. i called the local parts stores and none of them could test the voltage regulator. i'm going to go back later tonight and full current the voltage regulator again and check current on the digital.

i'm still looking for suggestions... please HELP!!!

 

You might have hit on something - you might try checking all the grounds, especially since there is a bit of corrosion.

 

since pulling the fuses didn't alleviate the problem, it'd have to be either the main ground (jumping with the jumper-cables didn't help, i'm still making a new cable), or a ground that was for something with a high draw that wasn't fused.

I pulled the starter wire (from solenoid to starter) in case the starter was drawing and checked for any change in current, but it was nothing discernible. Since its not drawing when the ignition is in the off position, it has to be something switched through the ignition. that leaves out the headlights, since they can be turned on even with the car off and the battery doesn't drain overnight. is it possible that the ignition is drawing an insane amount of current? could the DS box be going bad?

I'm getting ready to go out and make that new cable. i'll update when i figure out something else.

 

If you used the jumper over the existing cable, then it still needs to make it through the corrosion to make it to ground on the battery.

 

[SIZE="3"][I don’t believe your voltage regulator is bad.

I believe the ALT is not give full output, bad diodes or worn brushes will cause this.
This will show up if you can remove the ALT and have it bench tested at a auto parts store.

Also, your ALT is mostly like a 1G, which will not have much output at idle, it might not even keep up with the headlights at a low idle.

For your testing can you run it at a fast idle, 1500-2000 RPM?

Also test for a voltage drop between the ALT output stud and the battery Positive.
But the + lead on the ALT output stud and the NEG lead on the battery positive terminal. In a perfect world the voltmeter will read zero volts, but 0-.5 would still be OK.


JIm/SIZE]

 

I put the jumper cable from the battery cable terminal to the water pump housing. the cable terminal is a new lead terminal, and the water pump is new and pretty much corrosion free. it should have given a really good connection.

I had the alternator bench tested this weekend and it tested out okay.

i don't have a tach on the car, but i'll have my girl come out and keep it at a steady high idle for testing.


No problem, i'll check this at both low idle and high idle

 

I had my girl come out and hold steady at about 2G, cross terminal voltage remained relatively constant.

i checked voltage drop between + lead on output stud and positive terminal on battery. meter gave a reading of .008-.009, so minimal voltage

as an interesting side note, when i went out and checked the voltage before starting the car the cross terminal voltage was 13.00 volts. when i had shut the car off the voltage was about 12.6. when i turned it back on, it dropped down again to about 12.6, then stayed pretty steady. it only raised up to about 12.7 before i came back in.

 

My gut feeling is still that the ALT has a weak output.

 

i went back out an full fielded the alt again with the voltmeter cross terminal on the battery. with the voltage regulator disconnected i could hear the alternator spinning freely. when i full fielded the alt i could hear it reengage and the RPMs drop. the voltage briefly jumped up to 13.9-14.1 for approx half a second, then went back down to about 12.6-12.7. it would jump each time i full fielded it, but wouldn't stay up, nor did it appear to be charging or discharging at a rate any different than without the alt full fielded. i think i'm gonna try another voltage regulator. the new one is still under warranty anyways. it can't possibly hurt. i'll test the old alt when i go in also and see what its output is. i never turned it in for core charge, it just didn't feel right.

still, the jump from full fielding seemed suspicious to me

 

This sounds like the belt is slipping.


Does it do this at idle AND 2000 RPM also?
It should stay at 13.9-14.1 volts when you full field it and NOT drop back to 12.6 volts.

When the voltage drops back did the ALT spin freely or was it still loaded up?

Jim

 

My guess would be the voltage regulator, but that is only a guess. We have been chasing this around for a few days now. The alternator should put out a set amount of voltage, especially if you are seeing that spike, and you know it is capable of doing so. You might, on a whim, try a 3rd regulator. If the first one went bad, it is possibly you have replaced it with another new one that was bad.

 

I went to the shop again. Someone had suggested that it may be the ignition module (the DS box), so i had them test the box, it tested out fine. i also had them check the old alternator while i was at it, and to my surprise, it failed: putting out only 10 amps on the bench tester. i went ahead and turned it in as my core and bought another voltage regulator. i'll install it sometime tomorrow. got a service bulletin while i was there that clarified the wiring of the voltage regulator somewhat, so at least i can chase a few of the wires a little easier and check them for shorts. i'll post my results tomorrow.

a point i had failed to bring up before: this hadn't become an issue until the snow hit. the car had been running fine, but looking back it was right about the time of the first real snow that the car started not charging. i'm wondering if this may have something to do with the charging issue.

i'm also going to check continuity from the positive cable to negative cable. if there is continuity while the car is off, shouldn't this be a red flag as to a dead short somewhere in the system? is there any other way to determine if this could possibly be a dead short somewhere?

thanks again to everyone for all the help on this issue...