For as long as I remember, gas stations with car washes give you a discount if you buy 8 or more gallons of gas. Never had a problem with that until I got my Prius! I went to get gas and a car wash at the local Standard station yesterday. My gas gauge was between 1-2 bars and I never like to have the “flashing one bar”. I was filling it and it cut off around 7.8 gallons. I did a no-no and kept clicking it until I got it over 8 gallons so I could get the $2 discount on the car wash. I don’t know how many of that extra gas got sucked back in the exhaust hose.
So maybe it’s time that gas stations change this. Why not make it 6 gallons or more??