Puzzling Electrical problem
#1
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Puzzling Electrical problem
here's the thing... I start the car, and I'm getting a nice 13.5 volts, but as soon as I start driving and hit a bump or something, the volts drop down to below 12.
So, pulled the alternator and had it checked at the local auto parts store - checked good.
checked the wires coming out of it... replaced them. Still does the same thing.
I tried running wires directly from pos and neg on the bat to the two prongs on the alt and it worked, but the voltage wouldn't regulate. (voltage increased with RPM) Looking at the wiring diagram, it shows the alternator and Volt. Reg. as one assy. It doesn't appear that this is the case due to my testing methods.
Does anyone know where the voltage regulator is? Has anyone had a similar problem? I'd like to just run new wires to the V/R if I can.
Help!! this is the only VERY ANNOYING thing keeping me off the road!!
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So, pulled the alternator and had it checked at the local auto parts store - checked good.
checked the wires coming out of it... replaced them. Still does the same thing.
I tried running wires directly from pos and neg on the bat to the two prongs on the alt and it worked, but the voltage wouldn't regulate. (voltage increased with RPM) Looking at the wiring diagram, it shows the alternator and Volt. Reg. as one assy. It doesn't appear that this is the case due to my testing methods.
Does anyone know where the voltage regulator is? Has anyone had a similar problem? I'd like to just run new wires to the V/R if I can.
Help!! this is the only VERY ANNOYING thing keeping me off the road!!
#2
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The VR is internal in the alt. Hows the heavy black wire from the alt to the fuseable link block? Sounds like a bad connection in that circut, or your regulator is going south on ya.
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I had a problem with the relay on the front driver side of the engine bay comming out of the caseing and cause all types of hell. You might want to check that.
Oh yeah, try tightening your belts, it my be slipping *shrug*
Oh yeah, try tightening your belts, it my be slipping *shrug*
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Originally posted by Rx7carl
The VR is internal in the alt. Hows the heavy black wire from the alt to the fuseable link block? Sounds like a bad connection in that circut, or your regulator is going south on ya.
The VR is internal in the alt. Hows the heavy black wire from the alt to the fuseable link block? Sounds like a bad connection in that circut, or your regulator is going south on ya.
My choke doesn't work now, either... same timeframe with the problems.
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Nope, if theres a short you could melt a shitload of wires and possibly cause a fire!
I wouldnt do it, you wont be able to disconnect it fast enough. *poof*
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headlights work.. brights only work when you pull back on the switch, not when you push forward... that has to be the switch.
Hmm... I guess I'll be checking the Ground, Ground, Ground
Thanks, guys!!
Hmm... I guess I'll be checking the Ground, Ground, Ground
Thanks, guys!!
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well, you're not going to believe this, but it was the alternator... all 3 of the used ones I had.
I had replaced the one that had started to do this about a year ago with one from a 2nd gen. I forgot that old one was having the same problem... tried it, and another one that had like 200k on it. (why I thought it might work, I don't know)
Anyway, I decided to pull them apart, and I found the same prob on all of them.. the brushes were barely touching... on the one with 200k, they weren't and that alt didn't do anything.
So, 3 of 3 being bad.... I'm going to the junkyard tomorrow!! Hopefully I'll find a good used one!!
Sonofa....
BTW- I did check all the grounds, cleaned them up, checked the wires... It's all good.
I had replaced the one that had started to do this about a year ago with one from a 2nd gen. I forgot that old one was having the same problem... tried it, and another one that had like 200k on it. (why I thought it might work, I don't know)
Anyway, I decided to pull them apart, and I found the same prob on all of them.. the brushes were barely touching... on the one with 200k, they weren't and that alt didn't do anything.
So, 3 of 3 being bad.... I'm going to the junkyard tomorrow!! Hopefully I'll find a good used one!!
Sonofa....
BTW- I did check all the grounds, cleaned them up, checked the wires... It's all good.
#12
Bring your alternator to an automotive electrical shop, or someone who specializes in rebilding starters or alternators. You won't believe how much money you'll save vs buying an assembly line reman, plus you know what was replaced and that it was done right. Also you don't know what you gettin when you go to the junkyard. You have 3 cores, so use whatever has the most output and for god sake REBUILD IT!!!!!!!!!!!!!
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UPDATE!!!
Those of you who said "Ground, ground, ground" were right, although, it was the wire from the engine to the chassis that was the problem. The car works better now than it ever did!!
Also, during my crazed trips to the junkyard, I was with a Dodge fan frend of mine, and I happened to look under the hood of an 89 Caravan. Guess what? It had a Mitsubishi engine in it. It also had a Mitsubishi ALTERNATOR in it. Damned thing hooked right up electrically!! I had to file off the mount, a tiny bit to get it to fit on the water pump, and I had to cut out a notch on the bar that holds it on, but otherwise, it fit great.
You're probably wondering why THE HELL I thought it necessary to go through all of that trouble, right? Well, the sticker on the top that said 75 amps was one reason, and the fact that it already had a Dual Belt Pulley was another!!!!
I looked around a bit more, apparently, 86-89 Dodge Caravans all have these alternators. I highly recommend it!!
BTW: Chrysler and Plymouth had different engines and different alternators... I checked.
I'll post pics in another thread when I get batteries for my camera.
Those of you who said "Ground, ground, ground" were right, although, it was the wire from the engine to the chassis that was the problem. The car works better now than it ever did!!
Also, during my crazed trips to the junkyard, I was with a Dodge fan frend of mine, and I happened to look under the hood of an 89 Caravan. Guess what? It had a Mitsubishi engine in it. It also had a Mitsubishi ALTERNATOR in it. Damned thing hooked right up electrically!! I had to file off the mount, a tiny bit to get it to fit on the water pump, and I had to cut out a notch on the bar that holds it on, but otherwise, it fit great.
You're probably wondering why THE HELL I thought it necessary to go through all of that trouble, right? Well, the sticker on the top that said 75 amps was one reason, and the fact that it already had a Dual Belt Pulley was another!!!!
I looked around a bit more, apparently, 86-89 Dodge Caravans all have these alternators. I highly recommend it!!
BTW: Chrysler and Plymouth had different engines and different alternators... I checked.
I'll post pics in another thread when I get batteries for my camera.
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