You have to remember that the mid 1980's M-Benz cars were not made with gas mileage as the priority. Top speed and aceleration were more the norm back then. My 190e 2.3-16 only gets about 21 mpg on the highway and 17 around town. I am replacing the throttle position switch since I checked it out the other day and the small rubber boot around the switch was torn and the switch look corroded. Maybe this might improve the mpg's. My car has a minor idle problem, probably due to the car running in the limp home mode. Joe