MPG meter question

[bmwrocks]

If I am cruising down the road with some gas applied, then release the pedal to coast to a red light or the like, my MPG meter will drop all the way to left and stay there until I stop. But if I reapply gas before reaching the stop, the meter will move into the >30 range which is what I expect. Then if I release the gas again, the meter will stay in the >30 range until I stop and then return to "pegged left".

This is trivial, but doesn't seem right. Can anyone check theirs in a similar fashion to see if it does the same thing?

I wonder if it is affecting my overall MPG average reading (falsely raising it), or is that calculated separately?

 

[olcrazy1]

my MPG gauage was doing all kinds of starnge things liek that also.
I told the dealer of the problem, they re-programmed the speedo cluster under waranty and it has been fine since.

 

[codex57]

Mine will peg left when lifting off, but right before I stop, it'll flutter when it changes gears to 2nd (or 1st). If I apply gas, it goes to 30, but it does peg left again when I lift off. It does stay at 30 for a lil bit tho so sometimes it takes a while before pegging left again.

 

[Susie520]

I wonder why the worst "possible" MPG they have the on the meter is 12? When accelerating hard my meter stays at 12 until I let off the gas a bit .... I feel as though when I am giving it a lot of gas I am actually getting something closer to 8 mpg, so I'm curious why the range goes from 50-12 mpg. I only get 30 mpg when I am crusining in 6th and sometimes 5th.

 

[gizzy]

I think that once it can't calculate a current MPG (eg really slow speed, or zero mpg) it defaults to showing the needle all the way over to the left. At least that seems to be how mine works.

 

[jrt67ss350]

I wonder why the worst "possible" MPG they have the on the meter is 12? When accelerating hard my meter stays at 12 until I let off the gas a bit .... I feel as though when I am giving it a lot of gas I am actually getting something closer to 8 mpg, so I'm curious why the range goes from 50-12 mpg. I only get 30 mpg when I am crusining in 6th and sometimes 5th.

They probably don't put a mpg reading of less than 12 on the gauge so that people don't have a heart attack while test driving the car when they see that it only gets 7 mpg during acceleration.

 

[MrElussive]

I think it's just that it's kind of hard to calculate gas mileage during slower speeds, particularly in city-type driving. The MPG meter is more reliable for highway cruising...I will play with mine a little bit and let you all know how it acts. I like to have my MPG meter open while driving (I access it through the navigation) and I haven't noticed anything "weird" about its calculations, but I will look more carefully next time I use it.

 

[theBMWenthusiast]

ya, the meter is more correct for highway driving but it can give u in the area of what you are normally driving on the street