I just got my oil changed about 1000 miles ago and I noticed my mpg went from about 23mpg down to 18mpg. Nothing has changed whatsoever. Tire pressure is set with a digital gauge to 35psi and driving habits and places have not changed. Air filter is clean. I even tried running a couple of tanks of premium fuel in but it did not help. I always get my oil changed at the honda dealership. Any ideas? Its a 2005hondaaccord v6 auto.
