I have filled the car up to this level many times but who knows I will check it out. I have also had a electrical issue with my horn circuit that started when I changed my steering wheel. The horn went off on it's own last week while driving and I pulled over and pulled one of the wires at the horn. I haven't made time to address the issue. I sure hope it hasn't caused some larger electrical problem. As I said, my combo gauge glass was fogged up and I think this is the result of something getting hot under the dash.