When I filled up last Saturday, my mpg was 55. After 136 miles, it's now it's 43.7. Does anyone know why the big drop?

I had filled up in Woodland Park before driving down Hwy 24 home. Since then, it's been all city driving.

 

Did you go to a different gas station than usual? Did the gas have ethanol? Even so, I don't think 10% ethanol fuel would cut your mileage that much.

Did the recent rain affect your mileage? I would guess not, since we've had rain for a while even before your last fill-up. But did you just happen to be driving through heavy rain and wind for most of those 136 miles?

 

Hmm. May sound like a stupid quesiton, but do you have a flat tire?

 

No heavy rain/wind and no flat tires. Tire psi is 35 for all 4 tires. I don't think the gas had ethanol.

I forgot to mention that I was getting 55 mpg with 6 people in the car. The road was very winding. I find it ironic that I got better mpg with a much heavier load than normal.

 

have you tried inflating your tires to 40 psi?