Some of the time I was keeping up with him, but a lot of the time we were both on cruise control. This was when I'd only had the car for about two weeks.

My Dad does not commute. He works from home, so most of the time when he takes his MINI out, it's to run errands for awhile, traveling farther than I do each day.

I don't know about the ethanol content of the gas here (I live in WA). I haven't paid attention. I have mostly been using Chevron's supreme with Techron. I do try to drive without being too "jack-rabbity."
Both our MINIs are 2003 five-speeds with the sunroof. Our wheels are the same size and they are both official MINI wheels, but they aren't exactly the same style. His was built about 6 months after mine, I guess. His came from FL and had lower miles than mine. Mine came from NJ (we bought our cars from out-of-state because they were so expensive and hard to find in our area—it was cheaper to buy them that way and have them shipped in).

One difference is I have the heated seats and he doesn't. Does it take any gas to heat the seats? I did use the heated seats a lot in the winter time.

 

I would definately run some fuel system cleaner through it, it can't hurt. As far as every thing else everyone has posted I definately agree with the air filter/spark plug/ecu update suggestions. The only time I ever got less than 25mpg in my mini was when my rear caliper ws dragging. Honestly I have found the onboard computer to not be helpfull when calculating mpg. When I calculate mine and look at what the onboard computer says I'm 4+ mpg better than what it is telling me.

 

You can coast a longer distance if you do.

 

Techron is an "ethanol" like additive that helps clean the fuel lines. So if you have been using Chevron most of the time, the fuel lines/injectors should be reasonably clean as long as there isn't something very wrong with the car. A significant drop in fuel economy can be a symptom of something else.

The Ethanol is mandatory in all of Oregon all year now, new since last fall I think. I'm guessing that WA will have an ethanol content in the metropolitan areas, Seattle-Tacoma area and the such.

Strange thing about the ethanol mixed gas, it does burn cleaner, but you burn more of it to go the same distance. Kind of wash as far as the environment goes.

The cheapest and fastest test is changing the air filter. $8-10 at the Fife dealership, at least that is what they charge here in Portland.

The fuel, air filter and low tire pressure, altogether could account for the lower mpgs.

The bum warmers don't use gas directly, they do use a LOT of electricity which will keep the alternator running a full whenever you feel the need to warm your bum, which in turn sucks a little power from the motor, lowering the mpg.

 

Well, I took the car in today with a printout of this conversation and all the paperwork I have on the things that have been done to the car (the guy is a long-time family friend and had asked me to do online research before I came in, so it wasn't a case of me telling him his job—he was expecting it). He checked over everything he could think of and everything that was suggested here and found nothing. Everything is working the way it ought and is in good shape. He said it seems like it's just the car. He even suggested that I sell this one and buy my Dad's, which may actually happen because my Dad now wants a Clubman. We'll see what happens.

I'm thinking that there are a lot of variables (the snow we had this year, the hill I live on, my short commute, the car itself, the way I drive it, the heavy wheels with the snow tires, etc), and that the combination of them all just makes the mileage since I've had the car be 24 MPG. I guess I'll just try to drive it as best I can, not expect too much of it, give it some more time on regular tires and its aluminum wheels, and keep my eyes out for another MINI that I can upgrade to. I definitely don't want any other car than a MINI. I'd rather drive this MINI than another car right now, even if I'm not getting 30MPG in town.

 

+1 more on the O2 sensors, that'd be one of the first things i'd check after the air filter. g'd luck!

 

Wow! I guess my MINI doesn't get good mileage compared to what I have seen posted here.
I'm lucky if I get 330 miles to a tank full on a good week.

 

my 03 got about 32 average my 08 41 average

 

My '05 S gets about 26 MPG around town. It doesn't matter if I stomp it or take it easy - 26 MPG. On long trips I get about 32-33 MPG pretty consistently, cruising at about 72-75 MPH.

 

Check the fuel filter as well. Or +1 on that if it was said already.

Because 23mpg is horrible for a mini. I am averaging 23.5 in my 04 Corvette Z06. Mixed driving.

 

I am getting a consistent 26-27 MPG (City) in my '05 R53 S (100% bone stock BTW) manual MINI. I get about 315-335 miles per tankful, which is not bad at all for this car.

Mods, pulleys, etc give more power but do have an impact on mileage. Also wide, low profile tires and large diameter rims (17 and up) also affect fuel economy.

Your driving environments and habits behind the wheel also reflect on the gas needle.

I don't drive mine like a grand ma, but I don't drive it overly agressively either.

I am pretty happy with the fuel economy of this car.

I will say this.... One area where the second gen MINIs surpass the R53 is in the fuel economy dept. My Clubman S automatic delivers 33 MPG in the city and 38 in the highway with a 172HP turbocharged engine. You got to love direct fuel injected engines.

 

Same here. Your numbers pretty much agree with mine. I have 48K+ miles on my '05 and only 5K on my Clubman S.

 

Yikes! I just filled up and got (gulp) 20 mpg in my new-used 2005 MCSc! I have been in a state of shock all day. I'm not an aggressive driver (at least i don't think so, but I always beat the other moms back to school after field trips without trying). I do LOVE the high rev feel, so tach around 3k+ almost always. I drove 40 miles , 99% highway, after my fill up with 1.5 gallons - an improvement of 26 mpg.

Is it worthwhile to open up the air filter compartment to check it out even if i don't have a replacement filter?

When one says to "check the spark plugs" what is one looking for? Would a "bad plug" be obvious? IS this an easy DIY look?

What's involved with o2 sensor check? (and how much)

Thanks!

 

Yes, you can check to see the condition of the airfilter and see how dirty it may be.
You are looking for carbon build-up and or a very wet looking plug indicating that its running too rich.
You might also what to check that the gap is set correctly.
In most cases the answer would be YES.
I guess this depends on how handy you are and if you have a sparkplug socket but for the most part YES.
I don't think that you can DIY this one as a matter of fact in most cases
even the dealer will replace it to check for a problem.
I'm not sure on the exact price.

 

I can go about 450 miles on a full. This is at about 60Mph speed.

 

Spark Plugs are cake, Takes about 10 minutes to swap them out. Same with the air filter. O2 Sensors can be a bear to remove. Best let the shop handle that if you don’t have the rights tools.

RPM does impact the MPG. My wife is getting 18MPG city because she doesn’t shift. The Mini does such a great job revving it doesn’t communicate to you to drop the RPM's. I do 5th gear at 40 MPH all day and get into the high 20’s. On the highway I can get 39 in slow traffic.

 

Maggie is getting about 28 MPG on average. We have had her for just over a month and put 4k on it. The Wife and I both drive it to work as we have opposing schedules. I just took out the air filter and boy is it NASTY ! I don't think it's been replaced, AT ALL !
I am a former mechanic, major classic car enthusiast and have worked on / restored several cars.... this is the worst I have seen ! I have one coming in to my local NAPA this afternoon. I hope to break 30 MPG after that.

 

Congrats on the new car.

 

I didn't see your car's odometer reading listed in your post, so I'll assume it's in the 60,000 miles range.
Being that you bought the MINI used, you really don't know how it was maintained. Assuming the worst, you should get it to a mechanic you trust and have common 60,000 mile maintenance done. Such as: plugs and wires, accessory belt, cleaning the injectors, and check over the brakes, wheel bearings, half shafts, struts, alignment, etc.
Any of these things or a combination of them would effect you fuel economy.
Also make sure it's running on synthetic oil and maybe have the transmission fluid changed.

 

I CANNOT believe some of the miles per tank some of you get! I am so sad. I have never had a tank last more than 249 miles. I am in the same boat as the OP. I always average around 20-22mpg. I used some of that Bg44k engine treatment with little to no results. I will have to check the spark plugs and air filter and go from there I guess. Thanks for all the good info guys. And to the OP, I FEEL YOUR PAIN.

 

Check your tire pressure, too, especially if you have run-flats.

 

My 03 MCS got around 26 mixed, biased to local, when it was new. Dropped to 24 when I put on the pulley and software and CAI. Lately dropped to 21 when I put on DT Bypass valve, changed to NGK cold plugs with .040 gap and started getting a SES light off and on since I installed Milltek exhausst shortly after DT bypass. I think some of it is leaning on the loud pedal more with these mods, but also think either the DT bypass is guzzling fuel at low RPM's and/or bad-broken O2 sensor. O2 sensor might have gone bad from rich exhaust from DT bypass valve or maybe damaged upon exhaust install. Need to sort out in coming weeks. Any other thoughts?