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David Neibert
06-11-2009, 12:54 PM
Drove my 93 SC (turbo v8) to work a couple days ago to see how well the water wetter is working. On the way home I started having a string of strange things happen.

First part of the drive I was stuck in traffic idling for about 20 minutes and it started raining. When I turned on the wipers they seemed to be moving unusually slow. Then after getting onto the highway and up to cruising speed the Antilock brake light comes on..couple miles further down the road the radio suddenly shuts off, then the display on the radio comes on but no sound from the speakers.

Shortly afterward the VMM display starts flashing off and on then goes blank, a couple miles further down the road and my electronic boost controller display starts beeping and flashing then it shuts off. About a mile from home I pull up to a stop sign and can't see the reflection of my running lights from the car in front of me, but I can see them with the turn signal on. Half mile from home the motor starts sputtering and missing like it's running out of fuel, but the tank was just filled that morning. At this point it obvious that I've got a fairly serious electrical problem, and I shut off the wipers and running lights to conserve power.

I manage to keep the motor running by playing with the throttle and got the car into my driveway but don't have a remote opener in this car, so I honked the horn so my wife would open the door. Horn didn't work, so I put it in park and got out to open the door (raining pretty hard now) and the damn thing stalls. I get out and open the hood and everything looks normal and the new DCC Mrk 8 fan is blowing at full speed sucking the remianing life out of the battery. Tried restarting the motor and it barely cranked and then stopped and made a rapid clicking sound indicating a nearly dead battery.

Haven't had time to swap the alternator yet, but I did put it on a battery maintainer/trickle charger and even after being on the charger for over 48 hours it still isn't showing a full charge. Thinking the alternator is toast and may actually be pulling power with the car turned off. Even though it wasn't showing to be fully charged the car fired right up last night and everything was working fine. Checked the voltage and was only getting 12.0 volts at the battery and the alternator output. When shut off I'm showing 1.87 amps of load on the battery.

About a month or two ago I had the battery light come on at night while sitting at a stop light. When I gave it a little gas the light went off and never came back on. When I got home I checked the voltage and was only getting around 11.5 volts at idle, but 13 plus at 1500 rpms. I also found that one of the two main power wires from the 3g alternator had a broken terminal ring and the exposed hot wire was nearly touching the alternator case. I replaced the terminal lug and reattached the cable. The low voltage at idle was bugging me, but the battery always seemed to have plenty of power so I just ignored it and kept on driving the car. I'm now wondering if that broken power cable may have touched the alternator case and shorted out something in the alternator.

Weird thing was, the battery light never came on.

David

PS: Car never got over 185 and the fan kept working the entire time.

90coug
06-11-2009, 01:22 PM
Think a diode went out in the alternator?

Jeremy_K
06-12-2009, 03:39 PM
Sounds like the alternator is bad. My car behaved like that when I'd run the alternator underdrive pulley. It actually started bucking one day right from a launch at the track and it turned out to be the alt. I had brought it to AZ to get tested for the warranty and it kept passing the test. I would check it while the car was running and it was fine too. The problem ended up being when the alternator got very hot under load, it would shut down and that's when everything acted up. Those bench testers can't replicate those types of heat and loads so they always show the alt. as being good. I had to "alter" it a little for it to fail a test and get an exchange.

BuRHan90SC
06-12-2009, 06:37 PM
bad alty...do something about it before it get u stopped somewhere far :)

bowez
06-12-2009, 08:01 PM
This just happened to me a few weeks ago. I had a short and drained the battery ALT was good. Found short and new battery an was good to go.

Mike8675309
06-12-2009, 08:13 PM
You shouldn't have any load on the bat when off, and certainly not that much. Also, voltage should be better than 12. 12 is battery voltage, barely anything with an alternator running. Is that a single wire alt mod you have on there. If so, do you need to run the rpm's up to get the field energized and get the unit charging?

David Neibert
06-15-2009, 04:08 PM
Installed my Autozone backup alternator a couple days ago. Showing 14.5 volts at idle now and after 30 minutes on the battery tender it showed fully charged. Everything on the dash is also back to normal.

I had the battery tender running for over 48 hours with the old alternator installed and it never reached a full charge, so I'm sure it was draining the battery.

Sent the bad one back to PA Performance for repair under the lifetime warranty this morning. They even paid for the shipping.

David

Mike Puckett
06-16-2009, 11:02 AM
I don't understand why Ford didn't give us a voltmeter on the dash. I found one years ago that plugs into the cigarette lighter and it works pretty good. Harbor Freight has an LED voltage indicator that plugs into the lighter socket but it doesn't have a meter, only 3 LED's. On the other hand I just had to have the Caddy's battery replaced (fully covered under the Certified warranty). It was actually boiling the electrolyte in the battery :eek:, blowing out steam, and putting out 13.5 volts with the motor shut off after an hour's driving. Alternator was Ok.

kendall221
06-16-2009, 02:26 PM
I don't understand why Ford didn't give us a voltmeter on the dash. I found one years ago that plugs into the cigarette lighter and it works pretty good. Harbor Freight has an LED voltage indicator that plugs into the lighter socket but it doesn't have a meter, only 3 LED's. On the other hand I just had to have the Caddy's battery replaced (fully covered under the Certified warranty). It was actually boiling the electrolyte in the battery :eek:, blowing out steam, and putting out 13.5 volts with the motor shut off after an hour's driving. Alternator was Ok.

I think the vacuum/pressure gauge is in the place where the voltage gauge goes on an NA. I use a digital (LED) voltage gauge that I bought from JC Whitney about 5 years ago that plugs into the cig lighter plug. Within the last year, I saw a similar one that was LCD in WalMart.

Check out this Amazon link.

http://www.amazon.com/Vector-VEC008-Digital-Voltmeter-Volt/dp/B0002ISEQW/ref=pd_sim_auto_2

Mike Puckett
06-16-2009, 03:14 PM
That's the one I've got. I've had 2 problems with mine. The pivot where the gauge part attaches to the barrel that plugs into the lighter socket comes apart and has had to be glued back together and when the car's cold in winter it reads low and when it's really hot in summer it reads about a volt high. Otherwise I like it, especially for the price.

kendall221
06-16-2009, 04:32 PM
http://www.speedsolutions.net/cyberdyne-volt-meter.html


See link above. This is the one I've got that plugs into cig lighter. Like I said, I've had it about 5 years and no issues. It's a bit more expensive, but at the time I bought it, it's the only one I could find to plug in, and I was only able to find it in black bezel with red LED readout.

I've recently been watching it and suspecting an alternator that's also about to die. Sometimes it appears to be charging with 13+ volts, and then in the heat on my way home from work in traffic (with A/C running, blower going, and radiator fan running), voltage will suddenly drop to 12 volts or less. One afternoon was down to 11 volts. I got home, charged the battery overnight. Next morning, it was again charging at 13+ volts. It's done that now for several days. Alternator is a reman unit that's about 5 years old and has a lifetime warrenty (came from Advance), but it seems to charge fine when cool, so I'm guessing it will pass when put on their test machine.

KMT
06-16-2009, 04:39 PM
I use a digital (LED) voltage gauge that I bought from JC Whitney about 5 years ago that plugs into the cig lighter plug.

Check out this Amazon link.

http://www.amazon.com/Vector-VEC008-Digital-Voltmeter-Volt/dp/B0002ISEQW/ref=pd_sim_auto_2

http://ecx.images-amazon.com/images/I/31rs8KfsF7L._SL500_AA280_.jpg

Funny...I use that exact one in my SC. Wouldn't leave home without it :)

backtobirds
06-16-2009, 07:02 PM
Yeah I agree the alternator was bad. Battery alone makes 12v, alternator puts out ~14.4. To charge the battery. Maybe still keep an eye on the battery for a little bit; with car batteries they can be forever damaged if they are run completely down.

David Neibert
06-17-2009, 08:08 AM
It has finally stopped raining and it's supposed to get up into the lower 90s today, so I'm planning to drive it to work to test the alternator and the water wetter.

David

Jeremy_K
06-17-2009, 03:33 PM
http://ecx.images-amazon.com/images/I/31rs8KfsF7L._SL500_AA280_.jpg

Funny...I use that exact one in my SC. Wouldn't leave home without it :)
Wallyworld sells these too by their batteries $15 I think. They are awesome to have. I started having issues when I moved my battery to the trunk so I was using it quite a bit to help me diagnose problems.

J dot Miller
06-22-2009, 08:42 PM
The 3G alternator has a problem. When you run it over 5,200 RPMS they tend to die. I learned this with my Cougar where the 3G was stock. Almost after every dyno run I would have a bad alternator. I solved the problem with a Bullet 4G alternator that is designed for higher RPM's.

I am not sure that a 6G will solve the problem so I put the 3G in my SC. In addition, I did not not want to fuss with a custom bracket for the 4G. But after doing the 2G-3G swap I doubt it would have been much more work.
:confused:

grey500se
06-23-2009, 07:01 AM
The 3G alternator has a problem. When you run it over 5,200 RPMS they tend to die. I learned this with my Cougar where the 3G was stock. Almost after every dyno run I would have a bad alternator. I solved the problem with a Bullet 4G alternator that is designed for higher RPM's.

I am not sure that a 6G will solve the problem so I put the 3G in my SC. In addition, I did not not want to fuss with a custom bracket for the 4G. But after doing the 2G-3G swap I doubt it would have been much more work.
:confused:

Having the same problem, even though i have a SHO, after a few hard runs alt was gone, overheat i suspect, charging at 17 volts, let it cool down charges fine for about 30 seconds, thten back to 17, this is my 2nd one less than 2k miles, reman i think...gonna try and rig up an external regulator

David Neibert
06-23-2009, 11:55 AM
The 3G alternator has a problem. When you run it over 5,200 RPMS they tend to die. I learned this with my Cougar where the 3G was stock. Almost after every dyno run I would have a bad alternator. I solved the problem with a Bullet 4G alternator that is designed for higher RPM's.

I am not sure that a 6G will solve the problem so I put the 3G in my SC. In addition, I did not not want to fuss with a custom bracket for the 4G. But after doing the 2G-3G swap I doubt it would have been much more work.
:confused:

When I ordred the 3G alternator I told PA Performance I was revving this motor to 6800 rpms on a regular basis and they didn't indicate it would be a problem.

David

J dot Miller
06-23-2009, 07:53 PM
Having the same problem, even though i have a SHO, after a few hard runs alt was gone, overheat i suspect, charging at 17 volts, let it cool down charges fine for about 30 seconds, thten back to 17, this is my 2nd one less than 2k miles, reman i think...gonna try and rig up an external regulator

Could be. All I know is mine and those of a few other friends reported 3G alternator failure after extended dyno sessions over 5,000 RPMs. Here is more info (http://www.geocities.com/smithmonte/Auto/3G_130A_Alternator_Upgrade.htm).

I am interested in this external regular idea. Please tell me more... :)


When I ordred the 3G alternator I told PA Performance I was revving this motor to 6800 rpms on a regular basis and they didn't indicate it would be a problem.

David

This is my first PA-performance 3G. All the others were Ford remans or custom made. Didn't you get your last one from the same company? :confused:

David Neibert
06-24-2009, 12:05 AM
Could be. All I know is mine and those of a few other friends reported 3G alternator failure after extended dyno sessions over 5,000 RPMs. Here is more info (http://www.geocities.com/smithmonte/Auto/3G_130A_Alternator_Upgrade.htm).

I am interested in this external regular idea. Please tell me more... :)



This is my first PA-performance 3G. All the others were Ford remans or custom made. Didn't you get your last one from the same company? :confused:

Yes I got it from PA Performance, and they are fixing it under warranty. I think a broken power wire coming into contact with the alternator case caused the failure. They did have some higher amp units that wern't suggested for my application because they didn't put out as much voltage at idle.

David

J dot Miller
06-24-2009, 07:39 PM
Can they tell you what caused the break?

Interesting, maybe they make a better alternator than ford. Please keep us informed. :confused:

David Neibert
06-28-2009, 11:40 PM
Can they tell you what caused the break?

Interesting, maybe they make a better alternator than ford. Please keep us informed. :confused:


The tech notes on the invoice that came back with the repaired alternator said "found a shorted rectifier no signs of abuse covered under warranty" and there was no charge to me...even the ups shipping was paid. Very quick service too, had it back on my doorstep in less than a week from when I shipped it.

David