help voltage problem...please look--->

[lownslow]

hey so my car has been doing something totally wierd for like the last month or so...if im driving with no lights on like in the daytime the voltage will drop to like 12.6 i believe at lights n such and when im cruising if i hit the gas it will go to like 12.6 but when i let off the gas totally it goes to its normal spot at like 14.4. here is the kicker if the headlights are on (not just the running lights but the headlights) it will read at its normal 14.4 (and the engine sound like it speeds up or suttn) but when i shut em off and drive w/o them it does the voltage rise/drop thing again as i have previously explained. i want to fix this asap as it is not only annoying but i dont want to be left stranded on the side of the road. please help me out anyone have this problem before? all suggestions are welcome please help.

 

[Genuine Rolla]

Have you checked all of your grounds..?

 

[lownslow]

yes i also tested it a few times both the battery and alternator at auto zone and they come back fine (alternator was tested in car)

 

[AirRideCivic]

you don't need to worry about being stuck on the side of the road because of your battery. once the battery starts the car you're golden. alternater takes over and starts to recharge the battery. +1 for that. the only thing i can think is that you have a problem with your grounds.