...a dead or dying cell in the car battery. Of course you see better when vehicle is running because it's then measuring the charging power from the alternator, not your battery.
When I put the key in the volt meter reads about 9v and it's hard to start but once I get it started it jumps up to 14v I can put a volt meter on the battery and it reads about the same. As soon as I turn the car off the batterys volts slowly goes down. It's like something is on and drawing power. I have a new battery and had the battery and alternator checked. Both good. I have no idea what's going on.

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