What is the problem with my battery gauge?

[cmills26]

When I am in neutral sitting at a light, my battery gauge goes way down, like in between the N and O in the word normal. Plus my headlights and interior lights get really dim. I have put in a new battery like 1 year ago so I am sure that is not the problem. Could it mean that my alternator is going bad or my fuel pump is going bad? Any thoughts on this?

 

[S/CBlack95GT]

Does the car have underdrive pulleys?

 

[cmills26]

yes it does

 

[95BLKGT5.0]

Thats why the underdrive pulleys.

 

[cmills26]

I can see if the gage went down a little bit but not down that far, could it be something else?

 

[95GtTopLess]

mine does the same thing but i don't have pulleys.....any ideas