AlB

I have not reset my mpg average for about 10,000 miles. I do about 85% city and 15% highway. My computer tells me 19.6. I have measured on the highway using the computer and the calculator. The computer tells me 24.7 and the calculator is 23.8.
al

katheikia

I dont understand this "I have not reset my mpg"...Doesnt It need to be reset every time you restart the car, otherwise it stops computing?

MidnightRider

Something is very wrong. I have owned two 550s and both give similar MPG. On the highway I can get 25-26 with cruise control at ~80 mph. I never do pure city but combined driving I average 20-21. I have a heavy foot but confess that I don't alway sprint away from every light at full throttle. I recommend you get this checked out.

john verdi

Thanks for the inputs so far. On average, it seems that from 10,000 miles and up expect 17 to 25 mpg (same as EPA) for an average pace. With my driving style, I'd be happy with, say, 16 mpg at reasonable city speeds to 23mpg for high average highway driving.

Thanks MRV99, but clearly we did'nt expect Prius mpg. Range is the important issue here, and at 23 mpg and a small tank, that's only a prudent 390 miles between fill-ups. The 21 mpg at 70 mph this car is getting so far, with no A/C and a tail wind, makes this car less attractive for higher trip speeds than a Prius. Like BigWhup I was hoping never to find out how many mpg one might get at 70 mph.

Currently, after 750 miles driving 50/50 at Granny speeds, we have used 50 gal from fill-up to fill-up (no computer) for 15 mpg. Let's hope some extra miles will bring things into line with expectations.

Roleez

You also have to remember that you're still breaking in the engine which requires you to modulate the throttle and not hold a steady pace. This contributes to increased fuel consumption. Once the break-in is over, the engine will loosen up and the mileage that everyone's reported will become a reality. I admit that when i was breaking in my 550 in the first few thousand miles, I was getting 13-15 mpg city / 18-20 mpg highway! Nowadays, I don't get those figures ... unless my right foot is to the floor!

Landa220

My 2007 550i (28K miles) gets city/hwy loop about 19-20mpg. If it's more highway it's more toward 22+; more city it's more like 18 or so. All highway driving about 75-80+ mph gets about 24+ mpg.

I had to learn the best way to drive in the city though. Here's where the mpg guage came in handy. Basically I've learned that from a light, squeeze into it to get up to speed, 40-45 quickly. You'll notice the guage will be pinned to the right showing it's sucking gas. Then I can back off the pedal and maintain my speed quite efficiently. The mpg will be reading in the 25-30+ range unless I have to get back on it.

My testing shows this to be more efficient than taking my time "easing" up to speed which keeps my mpg guage laying in the 12mpg or less range. Give this a try. It seems to me the less time in the 12mpg range the better. Therefore I spend as little time as possible getting up to my speed then backing off the pedal to maintain the speed using very little pedal.

This doesn't work with my wife's car (little or no power, cheapo Saturn), but with the power of the 550i you won't waste time (or gas) getting to the speed limit.

Let me know how it works,
Good luck

Richard in NC

I got about 25mpg during break-in on the highway and as much as 27mpg highway since. That was on a trip thru the WV mountains averaging 75 mph!
My estimated range can be as high as 480 miles. I think I have gone 420 or more on a few occasions.
Try a steady state cruise at 70 or 75mph. Reset the trip and see what you get just cruising for the next 5-10 miles. That will be your best possible and should be at least 25mpg on level ground. Also compare the computer average for a tank full versus actual miles traveled per gallon to fill up. The computer is often 1 mpg optimistic. If more than that or its under estimating the MPG, the dealer can adjust it.

PS: In 6500 miles since new, my overall average is 20.6 mpg. Some nice highway trips helped but that also includes a weekend at the track with a 9mpg average.

sixcard

What is the input to that ?Energy Control? gauge on my Bimmer?

Many years ago I bought an MPG gauge for my 36 Ford flathead 60. It was merely a vacuum gauge connected [rubber hose] to the intake manifold. It was calibrated into MPG. No doubt it did indicate relative fuel use but hardly accurate MPG.

BTW the same input powered my windshield wipers!

AlB

I am not sure of your question. It doesn't stop computing that I can tell, but does take a long time to change. I never reset for trips or for any other reason for that matter. After my last highway trip my avg went up to 21.2 and has slowly gone down from there. Anyone else feel free to chime in with your experience.

GT Premi

Actually, you do! Just not fuel numbers.