Was running my car today, LM-1 wideband wouldnt warm up, said low voltage. Said battery power was only like 10 volts. Checked the battery with a tester while it was running and it was only at 10.8 volts. After I shut the car off, the battery read 11.5.

I run an msd box, and an A1000 fuel pump. The alternator doesnt have 1000 miles on it. The electric fan wasnt even on yet.

The only thing I can think of besides worn/weak alternator is the wiring I did from the alt to the bat. I was in Germany and couldnt get the right peice so I used a galvanized cable crimp to tie the wires together. Could there be some resistance there? I cant remember if the wires came in direct contact with each other.....

Oh, the gauge on the car has read weak for some time.

 

Sounds like it's not charging. Check the fuse for the fan(s) first, this can make them not charge because they don't receive 12V feedback. After that get your alternator tested, replace as needed.