Ml270 poor fuel economy

[Duncan.ml]

My ML has been running very well of late although in the last week it has become bad on fuel, but the week before managed to achieve 475 miles before the light came on.
I keep it well maintained and has been recently serviced. Temperature reads normal, so I've ruled out thermostat.
Could it be the MAF sensor? Changed this about 30k miles ago.

 

[oigle]

My ML has been running very well of late although in the last week it has become bad on fuel, but the week before managed to achieve 475 miles before the light came on.
I keep it well maintained and has been recently serviced. Temperature reads normal, so I've ruled out thermostat.
Could it be the MAF sensor? Changed this about 30k miles ago.

You are obviously looking at a very short period. I would run a couple of brim to brim tests before assuming bad economy generally. You say everything is running well so doubt you have a problem.