Quick charging question...

Thanks for all the input, I'm gonna read through everything you guys posted and start troubleshooting in the morning. Before I came in I did decide to check the battery, and it only has 12.4V when the car is off. Is there a chance the VR is just trying to get my battery up to 12.6+?

I swear the grounds are good. If the grounds were bad, it wouldn't charge correctly at idle like it does.

It was charging at 14V with the old ECU at my gauge in the car, but that thing isn't too accurate, and I haven't checked it with the meter in a while, so I don't know if it was happening for a while with the old ECU or not. All I did was put in the chrome box and a new wiring harness, and checked it with the meter to make sure it was all good, and that's when I noticed the 15V when applying throttle.