Hey all...

So I just passed my break-in miles on my last tank of gas... my mileage for that tank was awful (about 20mpg, I've been getting 22-23) due to my finally getting to nail the throttle a few times towards the end of the tank.

I wanted to see if my "normal" driving mileage was any higher after passing break-in for this next tank, so I've been purposefully driving average and rather boringly. The funny thing is, my mpg according to the OBC has been hovering around _18_ mpg... instant mpg reading concurs. I know the OBC isn't the most accurate source of data and all.... but it's always showed at least 21mpg average consumption...

Is there anything that could cause such a steep drop in mileage? Hearing stories of people averaging 25-27+ in a CVT on here has got me a bit worried there might be something wrong with my car causing such poor mileage. I've been filling up at the Kroger supermarket station, 93 octane premium.... should I try going down the street to Shell and/or Quicktrip and see if that helps?

Thanks guys...

 

I have a plain 5-speed Cooper, I only get around 20mpg. I dont worry about it. It seems fairly normal. If I go on a long highway drive I get low 30's.

 

I have a 02/2002 build MINI Cooper 5-speed, and I get 29 MPG in mixed driving.

 

I get about 27 or 28 mpg on my MCS. I drive it spirited at times but mostly a daily driver. I don't think I ever got less than 24 mpg. If I was in the teens, I would be at the dealership. I think something is wrong. Almost sounds like you are running too rich.

 

Yeah....

I'm thinking I'll wait until I drain this tank, fill up at a brand-name station and see how it goes. If the next tank is this bad I definitely think I'll be giving the service guys a call.

It also seems to have slightly lower performance during this period as well. I noticed on my way to work today that it felt like I had the AC on (as far as responsiveness) but in fact I did not. Hmmmmm.....

 

In my experience you cannot get an accurate measure of fuel consumption on just one tank because there are too many variables. Air density and temperature, how much time spent waiting for red lights, how spirited you were driving, city or highway or twisty driving, and the biggie is how full was the tank to start with and how full was it at the current fill up?

On both my MINI and my Z3 I’ve kept track of the odometer reading and fuel added since acquiring the cars. So far the MCS with JCW has taken 68.1 gallons in 1782 miles for 26 mpg. That is about 60% freeway (70-80 mph), 25% twisty (very spirited), and 15% city (normal old fart slow). The Z3 has given 22.1 mpg for a much different mix of driving.

Calculating each fillup gives figures ranging from 19.6 mpg to 29.1 mpg.The Z3 shows similar variations between tanks. IMO this variation is due more to the big difference between gas pump automatic shutoff points than to driving conditions.

As they say, YMMV!

 

" If I was in the teens, I would be at the dealership. I think something is wrong. Almost sounds like you are running too rich. "

If you only drive short distances in town, its easy to get into the teens. I drive 20 miles each day, it takes about 1.5 hours. And as I said I get low 20s.

 

Stock 03 MCS going to Vegas from San Diego taking it very easy:

48.5 MPH = 26.7 MPG

Vegas + add CAI, Throttle body, pulley, coil pack, wires, and plugs.

Coming from Vegas to San Digeo driving like I stole it (some tripple diget speed some slower but at 4500 to 5500 RPM:

63.6 MPH - 27.6 MPG

Earl

 

It has been my experience that the fuel economy on these cars gets a bit better the more miles you put on them. Somewhere around 4,000 miles they seem to flatten out to the mid to hi 20s in mixed driving.

My 03 MCS has about 4500 miles, and I've been averaging about 28 mpg for the last few tanks of gas. I do a good bit of highway driving and the first and last 15 miles of my commute is twisty mountain road...so it's a good mix.

At first I was in the teens fairly regularly, then moved up as the engine broke in more completely I think.

Good Luck.

 

>>I have a 02/2002 build MINI Cooper 5-speed, and I get 29 MPG in mixed driving.
>>

what are you using to gather this info?