I'm sorta having this problem too, at idle i'm hitting 11.7-9 volts and when i'm driving its about 12.7-9 i had my battery recharged at kragen, and alt checked there (have a lifetime warranty alt with them) and they said battery is good and so is alt. I tried to trade alts but they said the machine has to read it as bad, the guy told me if you can make the machine read its bad then i'll exchange it, so basically he meant to mess my alternator up. Any advice?

-Andrew

 

Hmm, where are you reading this voltage at? If at your gauge or turbo timer, etc..., put a meter directly on the battery terminals while she's running. You need at least 13 to 13.5v to even give the battery a decent charge.

You can also put the pos meter lead at the top alt terminal under the boot (the "charging wire location), and the neg lead to the engine and check it there. If it's good there, but not at the batt terminals, your wiring and/or grounds are in need of repair...

 

I'm reading this via my afc II, i've had problems recently where the battery wouldn't hold its charge so i had to put new terminals on and it seems to have solved it, but just having the low voltage gets me paranoid about stopping somewhere and the car dying off on me. How would i test the battery?

How would i do this too? Thanks alot wayne.

-Andrew