So I'm curious if I have a ford reman alternator problem. My combo is 2.8 4# lower and a 3.2 alt pulley. Normal driving I see anywhere between 12.5 -13.6 never 14 and never 11. Now at wot it doesn't always go to the higher side of the scale but also doesn't go lower either just always somewhere in the middle. Also at wot my a/f are normal so I'm not thinking it's going lean but would think that a brand new alt from ford and a new battery to boot would keep me a little higher maybe 13.8 -14.4. And volts threw my scanner at PCM are always .5 volts lower then actual system charging rate. So the scanner says 13.5 at PCM and voltmeter at battery and alt are 14.0
Alt issue?
- Thread starter whi tri
- Start date
Is this at wot and where from PCM via scanner or handheld or voltmeter?
As long as you dont drop down below 12V at WOT, you should be fine.
My tuner doesn't agree and this is why I'm concerned. And it doesn't help that I'm a mechanic and no other car that I can think of is allowed to charge 12v. It just doesn't make since that these cars don't charge 13.8 to 14.5
Mine stays around 13-13.5 at all times Via Aeroforce gauge which reads from the PCM. At a full charge my Optima only reads like 13 volts, I usually keep it on a trickle charger because it doesn't get driven as often and Optimas discharge pretty quick.
It should charge higher, but like I said, if you dont go below 12V then your fine. I think your tuner is being cautious which isn't a bad thing. You probably have a bad rectifier plate with some weak diodes. If you have a place local that rebuilds them, have it checked. Or, send me your alternator and I can have my guy do it. Mine charges over 14 Volts.
Yea I don't mind at all that he's being cautious. I had some new cables today that hopefully I get time to put them on rear quik. One will be a new ground from alt the chassis and the other being alt to fuse block. They are 2g. I already have my battery in the truck with 0g. And this is a brand new alt from ford so I won't be rebuilding anything since they'll give me another one. This is the second one since the first one had a bend shaft. Good times
I don't agree considering most batteries full charge is 12.5v+. If he's at 12v, he's running off the battery, not something I want to be doing at WOT, nor anytime for that matter. I agree with his tuner, see the below link if you disagree, nothing personal.
OP,
My Aeroforce reads .5v lower than what is tested across the battery. You lose voltage across connectors etc.
Start here for your testing http://www.svtperformance.com/forums/showthread.php?1005245-Charging-System-Test-Procedures
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Ok so I actually got a 3rd one from ford and they all are basically the same. What the hell is the odds of them all coming from the same batch! I mean really. This one will start at 13.8 and by the time the car warms up I'm down to 12.5 and wot 11. And if you turn on the lights and ac while idling once warm bam 11 volts. So pissed. So do I really just spend the money on mechman? I'm over this by now. I've replaced the feed cable and added another ground along with making sure all other grounds are good. Everything still points to the damn all but I've tried 3
At key-on engine off does the Battery light come on? If not check for a bad bulb in the IC.
Forgot to add, normally, a proper operating charging system should read between 13.5v to 14.8v.
Yes the light works and since I'm a mechanic and understand how the charging system is supposed to work is why I am still thinking I got 3 bad ones. It's very unlikely but also very possible. Nothing surprises me anymore. I thinks what needs to happen is I need to take a known good one off my friends car and throw it on mine to see
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