Just an update. My mpg has been pretty low. I just filled up last night and figured my mpg at 34.75 even though the reading on the car says 33.6 overall, and 37.8 for the past week. I hope the numbers go up

Anyway, I found out about MMT. Fuel companies started adding it after lead was banned as an additive. But the US has prohibitted the use of MMT in gasoline for decades, so it's not in the gas you'll find here. It has, however, been allowed in the fuel in Canada, and has been the source of controversy. At least it's one less thing I have to worry about