dancing battery guage

[lycan91]

my gauge jumps around its done it since ive got it, also when it does it, it kind of makes my lights go dim like as if i was turning them dim then bright. the guy said he had just put a new altanator (sp?) on it before i had bought it. anyone know how to fix this. i know the gauges are dummy gauges but with my lights doing that i know theres something wrong somewhere.

 

[Gatorblazer]

Have you tried cleaning or replacing the battery Cables? If that doesnt do it, take the alt off and take it to Autozone to have them test it. Mine did the same thing and it turned out that my alt was only putting out 10V. After two years of running it that way, it eventually killed the battery.

 

[lycan91]

i just replaced my battery few months back good thinking and have cleaned terminals numerous times

 

[ma96782]

Remove the alt and battery take them down to the auto parts place and have them tested (usually free).....while you have it off......clean posts and connections, inspect wires.

Go from there.

Aloha, Mark

 

[Gatorblazer]

Id have the alt checked just to be safe. Are you running any accessories? THey might be to much for the charging system

 

[lycan91]

Just 2 10inch subs and amp but it did that before i installed them

 

[shamaal]

my gauge jumps around its done it since ive got it, also when it does it, it kind of makes my lights go dim like as if i was turning them dim then bright. the guy said he had just put a new altanator (sp?) on it before i had bought it. anyone know how to fix this. i know the gauges are dummy gauges but with my lights doing that i know theres something wrong somewhere.

Actually the gauges are real, if somewhat uncalibrated. The oil gauge just goes to a switch, but if it goes to zero have it investigated.

Regarding the voltage, the most likely culprit as everyone else points out, is the alternator. Remove it and have it tested. Sounds like a blown diode or bad regulator. If bad, contact the guy and see if he can return it and take advantage of the warranty.

Other less likely, although plausible, possibilities are intermittent cabling or an intermittent short that does not blow a fuse.

 

[lycan91]

well i had read somethings on here about over/ underdriving its a newer altanator what if the pully on there is too big would that cause this

 

[lycan91]

 

[mall0y]

Not to hijack your thread but my 94 explorer (5 speed) is doing something similar. Whenever my RPM's reach 2500+ the battery guage starts dancing and the lights go dim. The only way to return the lights and guage back to normal is to let the RPM's drop below 2500. Anybody have any suggestions? My first thought was alternator but like lycan91, mine was just recently replaced also. Someome please help us out! haha

Ohh and by the way, I also had a stereo system (in signature) installed but I removed it because I'm at school. However, this whole thing started happening after the stereo was taken out.

 

[lycan91]

i dont see it as hi-jacking as long as its the same irritating problem. i would like to get this resolved.

as mentioned before seeing as how it is new and i read that the pulley can be to big on new altanators. so if i got a smaller pulley this would theisibly help right? and if not i can test the altanator. i just want some advice from some one that has had and fixed this problem.

 

[little x]

Does it happen only while idling, or while driving as well? I had this problem right when I installed my new alternator. And I disscovered that (for a different reason, the RPMs while idoling were dropping low enough that the alternator wasn't generating enought power. If your test yours, it's not hard to pull out, and it's bad I'll sell you my old one for $25 plus shipping (I think that's arround $15). Send me a message on cardomain if you want it. BTW my stock alt. pully is 2.5 inches.

 

[lycan91]

both i dont know if my rpms are too low they are probly 6-8k when idling

 

[Gatorblazer]

ID definatly have the alt checked just to be safe. Its an easy thing to do and it eliminates the alt in the troubleshooting guide. Check your grounds really well, especially with the sub system. Make sure that you grounded to metal and not just painted metal. Check your cables.
Im assuming that you mean 5-600RPMS on idle. That should be about right while in drive.