Greetings all...I just got back from a 600 mile trip (used it to complete my run-in miles) and am curious about my fuel milage. The best milage per tank I got on this trip was all interstate (not suprising), almost all sitting in 6th, never above 4500 rpm (pre 1200 miles) and yet my milage for this leg was only 27.77 mpg. I'm sure the window sticker said 25 city/34 highway. I'm getting between 19 and 21 mpg trundling around town. Is this common? Is it something that a software upgrade will improve?

On a possibly related note, I sometimes notice that when I'm accelerating past about 3000 rpm, I sometimes get a sort of hesitation in the engine tone. Kind of like a slight stutter. When it happens, it happens about 3-4 times, then the tone returns to normal. I guess I'm asking if this could be also a software issue?

:???:

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My Cooper S is FINALLY at home! It's almost as much fun as I had hoped, already. Once I get past break-in, watch out Las Vegas!! Liquid yellow with a black roof and bonnet stripes. The plates say MINIAC.

 

I don't know about the hesitation but the best I've gotten
in the S is a tankful at 24.9. I average around 21.
I think if I slowed down this would improve but the car
begs to be driven..

 

I went through brake-in in about two weeks. My engine has hummed like, I guess, the Newark Boys Choir, since day one. It screams occassionally as well, but never hitches, hiccoughs or anything like that. There is sometimes a little throttle lag until the computer understands I an wanting to accelerate quickly.

I haven't heard about this type of problem, but before you go crazy, also note that it is recommended you vary speeds and conditions during brake in. 600mi in 6th gear is the letter, but not the spirit, of the law. Maybe try 300 mi of secondary roads; lots of shifting, some fun, but not too fun acceleration.

My comp has never read over 28mpg, no matter what the conditions (3200mi, three 400mi plus highway days).

 

It could be the computer itself. reset the Odometer and see how far you get on a full tank!! And make sure your usinf premium gas!!

 

Based on my own experience in getting my DME software updated to the #31 version...
result = a marginal improvement in the engine stumbling issue, but now slightly decreased throttle response and slightly worse gas milage too!

I do NOT recommend getting the new DME software unless you think you REALLY need it.

Getting the newest software is an irreversible change.

 

Mileage gets better with time. Just turned 12K and I'm getting 32.8 MPG HWY.

I was getting in the mid 20's when the car was new.

 

I've never gotten worse than 22 and I drive pretty hard. I haven't had a full tank of hwy driving to check that, but I've never had a car that gets what the EPA says it should. Even my VW TDI only got about 34 (supposed to get like 40 in town).

 

I have gotten 32 mpg on highway and about 27 to 28 all around. MCS not a great gas mileage car. Great at other things like g forces. :smile: :smile: :smile: :smile:

 

Remember to compute your gas mileage using the old fashioned method of mileage driven divided by gallons pumped. Or remember to reset your computer after fill-ups. You could be getting better (or worse) mileage than you think.

 

Thanks for the responses. Let's see....I did vary my revs, gears and speeds until I hit the 1200 mile mark about 1/2 way through the trip. I didn't use the cruise control at all until the return part. I don't have the computer so all my milage is calculated by writing down my odometer at each fill, and dividing by the number of gallons input. I set it up in a spreadsheet so all I have to enter is the ending milage and the number of gallons and Excel calculates milage for that tank and updates cumulative milage.
I know that my milage will be lower than advertised since I tend to drive my cars pretty hard (accelerator seems to only have 2 positions - floor and off), and my commute is only 3 miles, but this seems to be quite a long way under what was advertised.
Oh yeah, I've only used premium gas in Alice. At 12 gallons a fill (average) and 20c a gallon more for premium, I'll pay the extra $2.40 a fill. I can save most of that by selecting the right part of town to be low on gas.