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Discussion Starter · #1 ·
The Voltmeter indicates that it's charging good until I turn on the a/c. Then it drops just below the discharge mark. If I turn on the headlights, it drops WAY down into discharge. If I turn on just the lights and no a/c, it still shows it's charging. This is the second alt. that I have put on it and it hasn't helped. Is there something I am missing that could cause it to do this? Could it be that the Alt. is just not powerful enough to power everything? I'm at a loss. Any help will be apperciated.
 

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How many amps is the alt you are using?? And is the gauge accurate? I would check it with a known good digital voltmeter. At idle with a moderate load it should be app 13.8-14.7 Volts
 

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The alternator is just adequate enough to keep up with the original equipment. You didn't mention if you've installed an aftermarket stereo headunit and/or amplifiers. With the tunes pumpin' the alternator is wheezin' like my fat butt climbing 4 or 5 flights of stairs. Lack of maintenance compounds the problem. What condition is the ground wire in especially at the ends? What about the connections at the alternator and at the starter solenoid? Clean 'em up and make sure they're good and tight and see if there's any improvement.
 

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Chandler is correct the stock 2.3 alt is bairly marginal at best. You can install a 3G that is 130 AMPS and a piece of cake to install.
 

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Discussion Starter · #5 ·
OK I finally got it tested with one of those big professional testers and it says that it's putting out 13.5 Volts. But it's an 80 amp alt. and with the test clamp around the wiring harness directly behind the alt. it's only putting out 70 amps. When you put the test clamp around the positive battery cable, between the battery and the Silenoid, it only reads 6 to 8 amps. And that's with no load. When there is a load like the a/c, even the turn signals take almost 10 seconds to flash. I'm thinking it would just be better to get a high-output alt. and be done with it.

And I don't have anything like an amp pulling on it. I haven't even turned the radio on in almost 6 months. All the connections are in good condition, clean and tight.
 

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Discussion Starter · #6 ·
Ok, I did alot of experimenting, turning on and off everything. It will charge as long as the a/c blower motor is not on high. With it on high it is in discharge, if I turn it down one to "Med-High" the needle moves up to the middle neither charge or discharge. If I turn it down again to "Med-Low" it will move up into charge alittle. If I turn it down to low it moves up to charge like the a/c isn't on. It me it sounds like the a/c is just pulling to much. Anybody else have any thoughts?
 

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Discussion Starter · #7 ·
I think this may be a short or something. On the way home tonight the tach went up to 3000 and the cruise control turned off. I turned off the a/c and the tach returned to normal and the cruise would come back on. I did this 3 times with the same result. On the 4th time the engine died. I let the car sit for about 10 - 15 min and started it again. It went back to the way I described it to start with. Don't know where I should start looking. Blower motor, A/C control panel or the compressor. This is really driving me crazy. Also if it helps the car has Dealer Installed Air instead of Factory Installed.
 

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Have the battery checked.

It is normal for the charge from the alternator to act "somewhat" like you are describing with the engine at idle, but when you increase the rpm to normal driving speed, it should be in the 13 to 14 V area of the meter. What are you calling charging and discharging? Is it dropping onto the red lines on the meter or staying on the green lines?

If your battery has problems, it could cause the symptoms that you describe. Have it load tested as well as the alternator. Free testing at most auto parts stores.
 

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Discussion Starter · #9 ·
OK, I put a aftermarket voltage gauge one it and it says it' s running between 13 - 14 volts. Unless the a/c is on high then it drops down to 12 volts. I replaced the blower motor and tested it just laying it the floorboard. It runs at 14 volts even with the a/c on high, without the squirrel cage on it. When I put the cage on it goes back down to 12 volts. And now the a/c compressor nor the cooling fan will come on. with out the compressor on it runs at 14 volts. what could be wrong with the fan and compressor that would keep both of them from coming on?

Also when the a/c is on and it's running at 12 volts, the "high speed" wire on the back of the control switch gets VERY hot. It got hot enough it melted the plastic connector that hooks the wires to the switch.
 
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