can someone tell me off the top of their head the volts on the car battery when the car is on and the volts when off? thanks for the help.

 

10.5-12V car off
and aobut 14.5 car on....correct me if i'm wrong somebody

 

those numbers sound "about right", I was actually thinking last time I checked mine, even with the car off it read around 14ish, but my memory is kinda foggy about it, the car may have been on... I'll go with him though. Funny enough, the voltage drop from there to the fuel pump is almost an entire volt too just FYI.

- Nathan

 

With the car off, it should read about 12V assuming you're not measuring thru some long, high-resistance wire. Best to measure right at the battery. With the car on, it should measure somewheres about 13-14V (you're actually measuring the output voltage of the alternator in this case, not the battery).

If you're seeing 14V with the engine off, you've either got a funky voltmeter, or something else is wrong.

 

well for the first few seconds after you shut off the car you will probably read 14v because there is still a charge in the alternator. once it disapates, then you will read around 12v.