It's only done it twice ever. In early September intermittently for about 3 hours. Then again on Saturday when I left a red light. It has never done it any other time. However, when we had the codes read at the mechanic today, and there was no code errors. However, he checked the old cleared codes (but we don't know from when) and there was an 1811 code in the old cleared codes. It has only happened twice ever.