Can some one give me an idea whats going on id dropped suddenly and i cant get it back i average 37 highway when its highway only and 30- 32 mixed i drive casually used to average 39 mixed and 44 hwy. cleaned the fuel system and still nothing the dealer i was using keeps blowing me off saying its normal and the other dealer doesnt seem to want to mess with it
I get much worse fuel mileage this time of year when the weather is cold. The car has to run rich while it's warming up and it takes a lot longer. Plus the winter gas mix is less potent with all the additives.
Not sure if this has anything to do with your sudden drop or not, just something to note.
Note: When the air is colder, it's also denser so the computer compensates by adding more fuel to achieve the correct air/fuel ratio. My car also runs much lower boost in the winter because it meets the desired torque figures much easier than the thin summer air. I max out around 10-12 psi in the winter rather than the 15-17psi in the summer.
To add some to this conversation: Winter blend fuel alone will lower the fuel economy. The stuff that goes in to lower the gel point also typically has lower energy - thus requires more fuel to produce the same amount of energy to move the car.
This has been going on close to 6 months its not fuel related or anything i can put my finger on but its way lower than what i should get an i cant get any dealer to lift a finger with it
I don't have a diesel but my guess would be something to do with the emissions system. Could be possible Regen issue. I assume you have a cat in the exhaust yet. Not sure what normal op ranges are but they will indicate if your cat is plugged up/burned up.
The dealer pretty much told me unless theres a light its operating fine, now i have a grinding noise and got a well we cant hear it drive it till it fails response even tho the service advisor can hear it