Mileage Sporadically Resetting on MFD

I'm not sure where this should be posted, but my MFD showed a mileage reset to 0 today. I only reset at fill-ups so that I can do long division.

Anyway, while trying to figure this out, I saw on the Consumption screen that the AMPG also started bouncing around. Before I shut off the engine, it bounced between 39 and 42.

Since the last fill up, the pips have been decreasing quickly...4 in 71 miles. I know the pips are not a linear measure, but 4 in 71 miles seems pretty quick.

Any ideas where I should start looking?

Maybe I accidentally tapped it with a knuckle, but I don't think so...

 

Glad to take the blame if it means that I can close this loop! I traveled less than 2 miles on the way to work when the miles jumped from 0 to 3 in less than 5 minutes...very curious behavior.

I've been reading up on gas tank bladder behavior during summer and winter months, about certain model GenIIs automatically resetting (though this confuses me...need to find out exactly what is known to auto-reset), and about just starting over (fill up, zero out trip, mileage, whatever) and monitor diligently. I always zero out on the Consumption screen; it hasn't auto zero-ed out that I've experienced.

According to my calculations, I've probably used about half a tank; so, in another 3 weeks (oy...i don't want to wait that long), I should be able to fill 'er up and start the sleuthing. I'll even turn the nozzle a quarter to the left or right as someone suggested to fill up as much as possible...and that's after letting the bladder breathe for a minute or so, as another person suggested.

Could my foam grill blockers be the culprit?

 

LOL. They do appear diabolical on the grill, like duct tape over a mouth...

 

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