2015 ML400 4Matic fuel economy?
 

Hey guys I am currently driving a '15 ML400 and I only get about 11-12 mpg in the city and 13 mpg city/hwy average. I do mostly city driving which I know will cause worse fuel economy but 11 mpg is pretty far off of the rated 18 mpg in the city from Mercedes. I also drive in comfort mode 99% of the time and have ECO mode on. For those of you who own this car what is your fuel economy like in when driving in the city? I suspect there could be something wrong causing poor fuel economy but I want to hear from other people who have the same vehicle before bringing it in to get checked. I don't know anybody that has the same vehicle where I live since most people buy the diesel version (ML350 Bluetec).

how often do you get gas?

There can be a lot of reasons. Have it checked out by the dealer or a good mechanic who knows German cars.

Are you usimg 93 octane? Try shell vpower or a top tier gas location.

For the next step
Try a Liqui molly fuel system cleaner or their jectron fuel injector cleaner.
You might have had bas gas causigg an issue.

Next....bad maf sensors can cause bad fuel economy too. But that's extreme. Cheap enough sometimes though to try.