Today I filled up my tank and after doing some math in my head, I came up with about 20 mpg. This gas mileage really hurts the wallet and it sucks. Why does the 2jz-ge consume so much gas? If the cause is the engine running too rich, then can't we lean it out some to get a little better gas mileage along with a slight increase in performance? When the corvette z06's gas mileage with a supercharged v8 is getting better mileage(on hwy), then you know something is wrong when an inline 6 isn't getting as good mileage.