We have a 2010 Fusion Hybrid with 19200 miles on it. Since we have had it our mileage averages 32.4 MPG. At times much worse. We took it to the dealer about a year ago for poor mileage and the instant mileage gauge jumping around. Of course the mechanic test drove it on a flat and level, no traffic route, probably acceleration like a turtle, came back and said he got 40 mpg. Finally a year later after the poor mileage came and went several times, the engine check light came on. We took it in and there was a erg code. The dealer did nothing except reflash the computer and gave it back. After two more trips to the dealer with the same song and dance, I asked them if they had any mechanics that knew how to acrually trouble shoot a car without a trouble code. Finally last week the mileage dropped to 26.5 MPG and the instant mileage gauge was erratic. The gauge which normally shows 60+ coasting downhill would sometimes only show 40 mpg. Took it into the dealer again and the ordered and replaced the egr valve. It seems much better and is getting better mileage. The instant mileage gauge is not erratic anymore. Haven't driven far enough to get a long term mpg reading. If the erg is not seating fully, it probably is messing up the fuel mixture, and if it really sticks open it will finally give you a error code.
