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  • 1996 - 2004 SN95 Mustang -General/Talk-
  • SN95 4.6L Mustang Tech

Battery Gauge

  • Thread starter Thread starter rjbonham
  • Start date Start date Nov 7, 2011
R

rjbonham

New Member
Nov 19, 2010
9
0
1
Nov 7, 2011
#1
  • Nov 7, 2011
  • #1
I have a 98 GT automatic. When I come to a stop light the battery guage drops sometimes to the point were the battery indicator comes on. If i put the car in netural the battery guage goes back up to normal. Any ideas.
 

wmburns

SN Certified Technician
Aug 14, 2009
5,892
514
204
Houston Texas
Nov 7, 2011
#2
  • Nov 7, 2011
  • #2
Start with the basics first. Are the battery cables clean and tight? Any corrosion at all? Is the negative terminal split?

Are the frame grounds around the battery clean and tight?

Next have the battery and alternator tested for correct output and excessive AC ripple. Almost all autoparts stores will do it for free.

Bottom line. Todays cars simply will not run right without a strong battery and charging system.
 
R

rjbonham

New Member
Nov 19, 2010
9
0
1
Nov 8, 2011
#3
  • Nov 8, 2011
  • #3
The cables are clean and tight. That was my first thought. The cables are in great shape. I will have the battery and the alt checked.
Thanks
 
R

rjbonham

New Member
Nov 19, 2010
9
0
1
Dec 21, 2011
#4
  • Dec 21, 2011
  • #4
Battery and Alt in great shape.
I have discovered that the battery indicator only goes down once the car is at running temp and when I come to a stop. I can put the car in neutral and the indicator goes up just a little bit. Once I give it gas it goes back up to normal range.
 

2vNotch

Active Member
Dec 6, 2011
519
21
29
Rogers, AR
Dec 21, 2011
#5
  • Dec 21, 2011
  • #5
U have any audio equipment running without a capacitor? Or powering multiple wires from fuse box?
 
R

rjbonham

New Member
Nov 19, 2010
9
0
1
Dec 21, 2011
#6
  • Dec 21, 2011
  • #6
Nope the car is stock. This started after I had to put on a new Idle contol valve.
 
S

Scott38060

New Member
Dec 12, 2011
2
0
1
Dec 21, 2011
#7
  • Dec 21, 2011
  • #7
I had the same issue on my 96 GT Convertible earlier this summer. In the morning or evening when it was cool, the car was fine. In the middle of the day, when the temp was warming up, the alternator gauge would begin a gradual decline until it bottomed out and everything electrical started failing on the car. The battery and alternator checked out great when the car was drivable and driven to the auto parts store. I took the alternator off the car and had it bench tested, and it checked out. But the problem kept recurring. So, I replaced the alternator AND battery, and have not had problems since. Not sure this is what you want to hear, but thought I'd share my experience. Good luck!
 
R

rjbonham

New Member
Nov 19, 2010
9
0
1
Dec 21, 2011
#8
  • Dec 21, 2011
  • #8
On my car it does not matter what the temp is outside. Everything works fine till car gets to operating temp. Then when I stop at a stop light the battery indictor slowly goes down. Only goes to certain point. Then when I give it gas it goes back up. Once in a while the battery light will flicker. I am not sure if the IAC replacement has anything to do with this or if it is just a fluck.
 

2vNotch

Active Member
Dec 6, 2011
519
21
29
Rogers, AR
Dec 22, 2011
#9
  • Dec 22, 2011
  • #9
The IAC shouldnt effect it unless theres any of the wires that may be exposed and possibly got moved around, and could b touching anythng it shouldnt (bare metal, etc)..??
 
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