I had the exact same thing happen to me a few fill-ups ago. In fact I believe mine also read .8 mpg on trip B. Kinda made me mad at the time. I'm now at 12.450 miles on the odometer, so it would have been around the same mileage as yours when it occurred. My current trip B LMPG is 29.8, but it should be 33.4. It was tracking my pump calculated mpg very closely.

Rich

Previous car - 2003 Civic Hybrid
LMPG - 47.1

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