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Charging problem... WTF is wrong? ONCE AGAIN

  • Thread starter Thread starter Stang8URMPRT
  • Start date Start date May 5, 2005

Stang8URMPRT

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Dec 28, 2003
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Daytona Beach, FL
May 5, 2005
#1
  • May 5, 2005
  • #1
Well, I know all my grounds are good. Today I took the car out and it was only giving me like 12.9 volts with NOTHING on. My autometer electrical was reading 210ish... Turn the car off... then back on right away.. back to normal! 14 volts with the electric fan on and now reading 185 degrees. WTF!!!!!!!!! Like I said, I've checked and all my grounds are good. wtfff is the problem here?! Any help would be appriciated.

Nick
 

5spd GT

"the 5.0 owns all"
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May 5, 2005
#2
  • May 5, 2005
  • #2
Well as some know I'm electrically retarted...but I had a situation where my "excitor wire" had shorted out and it was making me run straight off my battery and eventually I ended up on the side of the road at an animal hospital. I had to walk the rest of the way to school Luckily it was only a 1/4 mile away (how ironic)...but maybe the vibration from your engine starting/shutting off is making a similar wire make contact and not on occasion. That could be far out there...but who knows

I had to have my mechanic does some troubleshooting to find that it was the problem. It is the wire that tells the battery that the alternator will cover it from there (in simple terms).

Good Luck man...I know how that can be frustrating...
 

Stang8URMPRT

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#3
  • May 5, 2005
  • #3
Thanks David.
 

Grn92LX

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#4
  • May 5, 2005
  • #4
You jinxed yourself by posting that thread last week how you fixed the problem by cleaning your grounds (or whatever it was you did to your grounds, I forget) For sh its and giggles try what I did. I added another 4G ground wire from the power steering bracket (FMS a/c delete) to the chassis where the front swaybar bolts go. Doesn't have to be those exact spots, but you get the picture. I might add another 4G ground from the neg battery terminal to the chassis. Grounds are good
 

Stang8URMPRT

Active Member
Dec 28, 2003
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Daytona Beach, FL
May 5, 2005
#5
  • May 5, 2005
  • #5
Grn92LX said:
You jinxed yourself by posting that thread last week how you fixed the problem by cleaning your grounds (or whatever it was you did to your grounds, I forget) For sh its and giggles try what I did. I added another 4G ground wire from the power steering bracket (FMS a/c delete) to the chassis where the front swaybar bolts go. Doesn't have to be those exact spots, but you get the picture. I might add another 4G ground from the neg battery terminal to the chassis. Grounds are good
Click to expand...

Yeah, I did the same with my 83. But it was for added security, not for fixing any problems. Ugh... Let's get some more advise before I go buying crap lol.

Also, I PMed HISSIN50... I'll copy it in here, cause it includes more info.. maybe someone will beable to help with this info...

Hey. I just went outside with the multimeter again. I've been testing everything! There is barely ANY resistance from the output of the alt to the positive battery terminal with the car OFF... Now when I turn the car ON... There is about 400 ohms of resistance. Is this bad? I know my way around wiring things, but this is really pissing me off. I'm getting like 13.4 volts at the battery with the car on... and nothing extra on. Then the fuse box is reading around .5 volts LOWER... but then when I take voltage readigns off the back of the alternator, it's giving me around 13.7! This is all with the car up to temp, so I know it will put out lower voltage when it's up to temp. Man, anything you can help me with would be awesome.

Nick
 

jrichker

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#6
  • May 5, 2005
  • #6
Stang8URMPRT said:
Yeah, I did the same with my 83. But it was for added security, not for fixing any problems. Ugh... Let's get some more advise before I go buying crap lol.

Also, I PMed HISSIN50... I'll copy it in here, cause it includes more info.. maybe someone will beable to help with this info...

Hey. I just went outside with the multimeter again. I've been testing everything! There is barely ANY resistance from the output of the alt to the positive battery terminal with the car OFF... Now when I turn the car ON... There is about 400 ohms of resistance. Is this bad? I know my way around wiring things, but this is really pissing me off. I'm getting like 13.4 volts at the battery with the car on... and nothing extra on. Then the fuse box is reading around .5 volts LOWER... but then when I take voltage readigns off the back of the alternator, it's giving me around 13.7! This is all with the car up to temp, so I know it will put out lower voltage when it's up to temp. Man, anything you can help me with would be awesome.

Nick
Click to expand...
All resistance measurements must be made with the power OFF. If you leave the power on you get false readings or may damage the meter. Use the voltmeter to find votage drops across wiring & connections as shown it the picture, and do it with a good load on the system, like lights & A/C on, etc.



See http://www.fluke.com/application_notes/automotive/circuit.asp?AGID=1&SID=103 for help
 

Stang8URMPRT

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Dec 28, 2003
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Daytona Beach, FL
May 5, 2005
#7
  • May 5, 2005
  • #7
Okie dokie. So with my readings said above... is that a problem? Dropping that much to the fuse box? From the alt to the battery? WTF is the problem! It's really starting to piss me off real good.
 

Stang8URMPRT

Active Member
Dec 28, 2003
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38
Daytona Beach, FL
May 5, 2005
#8
  • May 5, 2005
  • #8
ttt....

With the car on and warm, and no accesories on, I'm only putting out about 13 volts at the battery. I'm thinking the alternator is already taking a dump. That and it's making a nice whining sound. I bought it from Alterstart on ebay and never had a problem with their products before... Lifetime warranty, but the damn thing is gunna be 30 bucks in shipping there and back.
 

HISSIN50

"How long does it take to get help in here?
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Nov 29, 1999
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May 5, 2005
#9
  • May 5, 2005
  • #9
how does the alt do when you put a load on it (tested at the back of the alt)?

if not so hot, a bench test, a phone call and off to the shipper.
 

Stang8URMPRT

Active Member
Dec 28, 2003
1,100
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38
Daytona Beach, FL
May 5, 2005
#10
  • May 5, 2005
  • #10
HISSIN50 said:
how does the alt do when you put a load on it (tested at the back of the alt)?

if not so hot, a bench test, a phone call and off to the shipper.
Click to expand...
Getting the same results, - about .1-.2 volts.
 
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