Hi. I calibrated my fuel tanks over the weekend. I have a RV-9A with capacitive fuel indicators. I have dual 4500's installed. I performed the calibration using 7 points, 3 gallons per point. I started with the right tank. The calibration process went smoothly up until I filled 9 gallons. When I filled to 12 gallons, the calibration signal, as viewed on the EFIS, would move up and down 10 - 20%, never really reaching a steady value (the aircraft was steady). This happened for the remaining points up until full. I ultimately picked a value that was in between he high and low.
The left tank did not exhibit this behavior. It was pretty solid all the way to full.
I drained the right tank to what should have ready about 4-5 gallons. It stayed high at about 12 gallons. The left tank tracked fine.
The next day, I ran the engine off of the left tank, it tracked fuel usage pretty well. I noticed the right tank jumping around from 10 - 12 to 4 - 5 gallons.
Thoughts? I am including the calibration data and engine system log for your review. Thanks