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Discussion Starter #1
hey all, the other day i noticed when i turned on the a/c my voltage would drop from 14 to around 12 with car idling. after driving and getting rpm's up voltage would come back up to around 14. at night with the lights on and a/c on the voltage drops to around 11 volts and engine seems to idle hard to stay at 700-800. i hooked up a dmm to the battery in the driveway to see what was actually happening and its pretty much the same when i cycle from a/c, headligts etc.. then when the cooling fan comes on the car almost wants to die. any thoughts on what should be replaced? im pretty sure the alternator/regulator are original to the car (93-2.3-172,000 miles) thanks in advance.
 

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Good call TOY but he is serpentine driven. Its dought full but could be. I say UP grade to a 3G and be finished with it. His alternator sounds KAPUT. Peace Tom
 

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i just done a 3g swap 2 days ago and im soooo impressed with it. best money ive spent yet! easy swap and cheap from a junkyard.
 

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I was taught that to find out if alternator is bad you start the engine and disconnect the positive cable from the battery. If it keeps running the alt. is good....if it dies the alt. is bad. Could one of you old timers clarify for us younguns?;)
 

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I was taught that to find out if alternator is bad you start the engine and disconnect the positive cable from the battery. If it keeps running the alt. is good....if it dies the alt. is bad. Could one of you old timers clarify for us younguns?;)


Oh hell no. Here we go again.:hihi:
 

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Discussion Starter #7
thanks for the advice guys. Turbo, what kind of car did ya pull the 3g alt out of? what will i be lookin for/at as far as getting the right one as i really dont want to buy a new one just yet. and yes tom your correct on the serp belts.
 

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I was taught that to find out if alternator is bad you start the engine and disconnect the positive cable from the battery. If it keeps running the alt. is good....if it dies the alt. is bad. Could one of you old timers clarify for us younguns?;)

ONCE AGAIN IF ANYONE EVER POSTS THIS DANGEROUS AND INSANE TEST PROCEDURE I AM GOING TO SCREAM.


Its dangerous its wrong and it can burn out every electronic part in the car. I think a sticky should be added to the site about this very dangerous procedure. Anyone that does this should be working in WALL MARTS Not on cars. This is scarier (THAN A THREE LEGGED CAT IN A DOG POUND)

TIP DON'T DO IT DON'T DO IT DON'T DO IT DON'T DO IT DONT DO IT DON'T DO IT DON'T DO IT DON'T DO IT DON'T DO IT DON'T DO IT DONT DO IT DON'T DO IT DON'T DO IT. GOT IT!!!!!!!!:nono::nono::nono::nono:
 

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Thanks;) Guess I never read throuhg all the alternator posts;) Guess you could have just used this smiley>>>>:nono:
 

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Thanks;) Guess I never read throuhg all the alternator posts;) Guess you could have just used this smiley>>>>:nono:
NO worries DUDE just do not want anyone HURT. A battery explosion can happen and ruin you DAY. PEACE TOM:bigthumbsup:bigthumbsup:smilie:smilie
 

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I agree with Big Letters. The alternator can generator a large voltage above 12vdc. If you take the battery cable off the alternator now thinks battery dead and kicks in majorly. Guess what overvoltage. There goes everything electrically. Also the spark at battery can make it BLOW UP.
Been there done it to me. I was jumping a old truck when younger. Putting the cables on the battery. [This is reason they say to ground to metal of vehicle] Remove the cable and blew side of battery off. It could have been top. If it had been top I would have been wearing battery acid. I got real lucky. Use care do it the correct way. Maurice
 

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Go to Stinger performance and look in their tech articles. Great write up on 3G alternators. The 1G alts are junk, 3G best upgrade EVER !! I used a 94-98 3.8l Mustang alternator.
 

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Applicable 3G swap candidates:

1992-1994 FORD AEROSTAR
V6 3.0 Liter FI - 182 CID VIN U O.H.V.

1992 FORD E-150 ECONOLINE
V8 5.0 Liter FI - 302 CID VIN N O.H.V.
V8 5.8 Liter FI - 351 CID VIN H O.H.V.

1993 FORD E-150 ECONOLINE
V8 5.0 Liter FI - 302 CID VIN N O.H.V.

1992 FORD E-250 ECONOLINE
V8 5.8 Liter FI - 351 CID VIN H O.H.V.
V8 5.8 Liter FI - 351 CID VIN H O.H.V.

1994 FORD E-250 ECONOLINE
V8 7.5 Liter FI - 460 CID VIN G

1992 FORD E-350 ECONOLINE
V8 5.8 Liter FI - 351 CID VIN H O.H.V.
V8 7.5 Liter FI - 460 CID VIN G O.H.V.

1993-96 FORD E-350 ECONOLINE
V8 7.5 Liter FI - 460 CID VIN G O.H.V.

1995-97 FORD F-250 PICKUP
V8 7.5 Liter FI - 460 CID VIN G O.H.V.

1995-97 FORD F-350 PICKUP
V8 7.5 Liter FI - 460 CID VIN G O.H.V.

1996-97 FORD F-450 SUPER DUTY PICKUP
V8 7.5 Liter FI - 460 CID VIN G
 

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Discussion Starter #16
well i gotta do something soon as on the way home from work tonight with the a/c, headlights and just radio on, sitting at a stop light (at idle) the voltage slowly started to drop to just over 10v until i noticed and revved the engine. i like the idea of the 3g swap and getting the increased output. i dont like it because of the cutting/splicing on the cars harness (from what i read) as i inherited it from a passed family member and kinda want to keep the car as original as possible ( i know i can get a junkyard mount and all that) i dont plan on ever putting much more electronically on the car if anything. surely the alt manufacturers have done something in the last 18 years to make the direct replacement alts better? (plus cheaper at local part store and in stock). damn its late.... am i making any sense haha. thanks for all the help.
 

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It may seem like a bear to cut in a 3g but it is sooooooo worth it. I went through 2 stock alts , both new, and ended up doing the 3g . Best money I ever spent. Even though your not adding a stereo or other electric drains the 3g is the best bet. Good luck,Greg
 

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Discussion Starter #19
thanks for the advice greg. here is where im at, took stock alt to parts store to get replaced. they tested it twice and said it was still working like new. brought it back home and took the battery back to be tested, again like new. its hot as hell here in tx so they seem to think with everything on its quite a drain on the batt/alt but they still work good so i guess ill just leave em in and wait and see. thanks all
 

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Ditto on the 3-G. Piece of cake to do. I went the j-yard method. Easiest mod I did on car. And a alternator can test good and be bad. I had 2 of the stock ones do it. I have had 4 stock ["rebuilt used with rebuilt tag my thoughts"] one's on mine go bad. The stock [lifetime warrant] is under my workbench and used one is on car. I trust it more. Maurice
 
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