Just swapped my engine and got it running pretty well today. I took it for a drive and all was good. Then my battery starts to die. So i rev it up a little bit, hoping that it would charge the battery enough to get me home. It dies. i roll start it and continue. The battery was about to die again, the lights were dim as hell. So i pull off the road and let it sit for a minute. Low and behold, the car started charging. It continued to stay charged at low rpm (under 2k). Anyone know what this is?

 

Grab a multimeter and test the voltage at the battery while the car is running. it should be putting out 13.5 volts minimum or higher at idle.

 

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