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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

help???

  • Thread starter Thread starter stangy50
  • Start date Start date Aug 24, 2004
S

stangy50

New Member
Aug 24, 2004
4
0
0
Aug 24, 2004
#1
  • Aug 24, 2004
  • #1
i have a 1990 5.0 lx with a cat back exhaust and a k&n. those are the only performance upgrades but i have a porblem that hopefully someone can help me out with. ok here it is when u r just drivin the car and the rpm's go over about 2800 the battery light goes on and the needle of the battery gauge immediatly goes to the top of the gauge. i have no idea what is causin this and if this is a serious problem. so if anyone knows whats goin on and can help that would be great cause i have no clue. thanks
 

04sleeper

Founding Member
Jun 22, 2002
2,674
14
89
Dallas, TX
Aug 24, 2004
#2
  • Aug 24, 2004
  • #2
Sounds like your voltage regulator is not working properly. Unfortunatly it is internal (inside your alternator).Try bringing it to a local auto parts store that can bench test it for you or you can bring it to an alternator shop to have fixed or if you feel comfortable enough then you could just rebuild it your self. Or go buy a new alternator.
 
J

jerry beach

Founding Member
May 20, 2002
2,671
0
46
Ocala,FL
Aug 24, 2004
#3
  • Aug 24, 2004
  • #3
Sounds like an overcharge condition to me. There is a voltage regulator in the alternator, it can fail and cause the alt to put out too much voltage. Remove the alt. and have it tested or take the car to someone who can diagnose it properly. This could result in a fire at the very worst, so it is very serious.
 
S

seijirou

Founding Member
Aug 15, 2002
2,417
4
48
DFW
Aug 24, 2004
#4
  • Aug 24, 2004
  • #4
These guys are rght, it sounds like the voltage regulator. Batteries really don't like seeing more volts than their designed for, and they can explode as a result. This is defanently serious, get it fixed before drivin' the car again.
 

04sleeper

Founding Member
Jun 22, 2002
2,674
14
89
Dallas, TX
Aug 24, 2004
#5
  • Aug 24, 2004
  • #5
I had a voltage regulator on my 82 go out and the top of my battery blew off! Battery acid all over my engine. Had to replace all my hoses, plug wires, battery, and battery cables.
 
S

stangy50

New Member
Aug 24, 2004
4
0
0
Aug 25, 2004
#6
  • Aug 25, 2004
  • #6
thanks for everyones advice the cars in the shop right now. so hopefully that fixes the problem.
 
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