Do I need a new alternator?
 

Battery at rest =12V
Idle 950 rpm no load =13V
Idle 950 rpm with load =12.2V (high beams and radio on)

Same numbers with and without load at 2000 rpm's also.
I'm pretty sure the answer is yes from what I've read in the archives....
Maybe I'm wrong?:(
Thanks,
Drew
86 930 Autronic EFI

No you need a new battery... Try charging it up overnight with a charger,
The fact that you're getting an extra 1V is indicating it's charging,, You may have a dead cell as it should charge to 12.8 volts or so

Off to the garage to charge overnight.......
Thanks

Check all your connections as well, including the starter. That's where I found my problem.... after I swaped out my alternator. :(