I was pleasantly suprised last night on the first long freeway drive.

But, I almost cant believe it.

65mph, AC on, POORING RAIN, 37.5 mpg average on a 100 mile round trip.

Can that be right??? We have an S with 34K on it, new tires, all evenly inflated to 32 psi (cold).

I was TRYING to get good milage, 6th gear, coasting, no unneeded flooring it.

but man, this is amazing.

 

Mine reads 11% optimistic on average.

 

It's usually a couple mpg optimistic. I suggest tracking by hand if you want to be truly accurrate.

 

still, 11% optimistic...thats 33mpg, with AC on, and torrential rain, that sould be about 37 or 38 on a dry day with no AC, I am pretty pleased.

 

Mine's usually about 1-2 mpg's optimistic. Calculating by hand is best.

 

I don't use the MPG feature on mine... But I use the range a lot!!

And it is looking quite accurate on my car...

 

Within 1.5 MPG, the speedo read about 2.5 MPH fast per my GPS

 

Is the question about the trip computer or the OBC MPG computer????

My speedo is about 4mph off at 65MPH (6.25%) which means my trip of 100 miles is really 94.75 miles so if I were you and I put in gallons then yes it's accurate 2.526 or 2.527 gallons depending on the pummp then the OBC calculations are right.

 

A few weeks ago I did a 300 mile drive from Virginia to NJ and tried to milk the car for maximum mileage. Now, I have a Feb 2006 MCS JCW that I have assumed will routinely get probably the worst mileage possible among MINIs - Cabrio S (with top down the whole way), JCW, Chili Red, etc. - but I generated a solid 33 mpg on that trip, and tickled 34 over most of the day.

Those numbers are from the OBC - but I have the raw mileage and gas numbers recorded to work out the real mileage (will report back later on that).

Around town - with all the fun I have on local roads - I am routinely getting 22 to 24 from the OBC. I am generally not at all unhappy with the mileage generated by this wonderfully zippy little vehicle....

Bill