Hey guys I am currently only getting about 12.5mpg in town with my bone stock ls2 powered v. This is with driving it like a grandpa. I had the p0171/p0174 lean codes and have checked over everything and cleaned the mass airflow sensor and the code has gone away but the mileage sucks. Mpg is only about 20 on the interstate. Had the car about 2 months now like the car but think the mileage should be better. Car has 95,000 miles on it.