MPG keeps getting better and better

I'm also seeing improved mileage. I started with 24-25 city and now I get 26-27 (this is without AC). AC brings back mileage to 24-25.
 
I agree, when your tank is filled from nearly empty you can sometimes notice a fuel quality difference (either in MPG or subtle differences in the smoothness and response of the engine). When the tank is still almost half full when refueling the dilution of the new fuel makes differences much less noticeable.

The last tank (and the last 4 of 5 tanks) was unbranded 87 octane with which I've been getting consistently good results. I think it's a good strategy to stick with a station that you've been getting good results from (but switch as soon as you notice less than ideal results). You may find the station that was not so good last month is now excellent. But convenience plays into it also since I refuse to travel out of my way simply to fuel.BTW, my complete fuelling history is available via my Fuelly sig (only visible on the first post on each page).

Good point. Its not just the brand of gas but also the "station" you choose to maximize those MPGs. I car pool with my wife. My computer is consistently averaging 30mpgs in mainly city driving. I drive a good deal at roughly 40 miles a day at 35mph speed average. Not sure if the computer recalculates upon AC usage but based on how often I refuel its actually in the 26-27 range.

Fortunately for me, there are tons of gas stations on my route home or to work.
 
Not sure if the computer recalculates upon AC usage but based on how often I refuel its actually in the 26-27 range.

The computer does take into account the effect of the air conditioner on MPG due to the way it uses the fuel injection pulse width to calculate consumption.
 
Just got back from a trip to Maryland. Averaged 32.5 on the way there (constant stop and go on the NJ Turnpike attributed to this) and 36 MPG on the way back! (well partially, filled up on the way and drove 120 miles on it) this right after I took to the roads from my 10,000 miles service :) also the gauge was 99% correct as the actual MPG was 32.4 according to fuelly. Gauge still reads 36 MPG but with almost a full tank that is sure to come down before next fill-up. Very happy with my first long highway trip. Was a good one.

BTW on the way back it was heavy rains the whole ride and I had the AC on at times to keep the front windshield from fogging up.

cx5mpg2.jpg
 
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It's always puzzled my why a car's trip computer mpg readout is not exactly accurate. The ECM knows exactly how much fuel is used, based on the injector pulse trigger width, and the distance measurement is at least as accurate as the odometer. Divide one by the other and quod erat demonstrandum!

From what I've read, it seems the CX-5 computer is pretty accurate (not done enough miles to verify myself), but my previous cars (Audi with multiport FI and GM with DI) were both horribly inaccurate. What gives?
 
The computer does take into account the effect of the air conditioner on MPG due to the way it uses the fuel injection pulse width to calculate consumption.

Well thats a welcome feature considering I live in the middle of the desert. Yesterday was 108 degrees. It's gonna be 110 degrees later this week. Again I drive 40 miles total on weekdays car pooling with my wife. All city driving. Got 32 MPG's average the last 2 days with AC on. Two things that are impressive thus far:

MPGs: The MPGs have been better than advertised in our experience. One thought why I'm pulling good MGs number are driving style. I coast at roughly 5-10 mphs over the speed limit. I also break by coasting and merely accelerate gradually from stop lights. Another thing too is I don't do access freeways on my daily route so I'm taking full advantage of the CX-5's low drag co efficient specs. On the freeway at 70+ mph, crosswinds mess up your mpg stats. Additionally I have a FWD with 17's so maybe there's the less weight and rotational mass too.

AC Unit: The AC unit on this car works fast to cool down the vehicle. It's a big plus that I've got a garage at home and garage parking at work. Shaded, I usually turn on the car and set AC at lowest temp at highest fan setting. I wait outside for for 3 minutes to allow seats to cool off. Cloth seats cool off much faster too. Then while driving I set AC setting a bit warmer and keep the fan at a low setting. Good to go while its 108 degrees outside.
 
It's not extremely accurate in my car. Mine usually shows between 1 and 2 mpg better than actual. I'd say it shows 1.3 mpg higher than actual most of the time.

It's always puzzled my why a car's trip computer mpg readout is not exactly accurate. The ECM knows exactly how much fuel is used, based on the injector pulse trigger width, and the distance measurement is at least as accurate as the odometer. Divide one by the other and quod erat demonstrandum!

From what I've read, it seems the CX-5 computer is pretty accurate (not done enough miles to verify myself), but my previous cars (Audi with multiport FI and GM with DI) were both horribly inaccurate. What gives?
 
It's always puzzled my why a car's trip computer mpg readout is not exactly accurate. The ECM knows exactly how much fuel is used, based on the injector pulse trigger width, and the distance measurement is at least as accurate as the odometer. Divide one by the other and quod erat demonstrandum!

From what I've read, it seems the CX-5 computer is pretty accurate (not done enough miles to verify myself), but my previous cars (Audi with multiport FI and GM with DI) were both horribly inaccurate. What gives?

Because the injectors vary. There are companies that will test the injector flow rates and show you what they really are, and allow you to match injectors. They can vary by a couple of percentage points. Plus, as they age, their flow characteristics change. So, the fact that the CX-5's computer is with in a percent or so is pretty good.
 
Just filled up today and had a best yet reading of 7.9l/100 on the trip meter. It calculated out to 7.84 or 30.1mpg If I had added a little extra fuel after the shutoff it would have been even closer. On any given tank of fuel a lot depends on where you fill up, how much you top off after the initial pump shut off, how fast you are putting in fuel etc. In the long term the averaging of these factors should reveal the true accuracy of the on board meter. So far it seems pretty close on my car. It seems I can get better milage on secondary roads at 40-50mph than on the highway at 65-70. I have yet to go on a long trip to test that theory.
 
I've had consistent 29-32 mpg avg in Southern California with a good amount of hills and aprox 50% city and 50% freeway (68-78 mph and polar opposite sub 20 mph crawls during rush hour). I've been looking for non-ethanol blended stations, but no luck in the LA county area to test if there is improved mpg.

As far as the onboard computer readout... In my case the mpg displayed is usually conservative and when calculated based on gas used when filling back up to a full tank and mileage driven on the odometer I get 2-4 mpg more (29-35 when I calculate it), only once it was 2 mpg worse than displayed.

For reference I have a 2014 GT FWD with just under 3k miles.
 
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Good afternoon
I have a CX 5, 2.0 2wd, i love my car, but i dont have the same fuel economy, is very sad, and i dont know what to do, because my car just give me 27 Kpg, im waiting because its new (only have 2645 KM) but ist the same, i dont know if anybody have the same problem?, the dealer have right now my car cheking if something its wrong with the car computer, this its my first post in this forum, and its good share with other CX 5 owners, i love my car, and im very happy with it, just that problem make me mad, sorry for my poor english but actually i speak spanish and this is the more complete forum i cut find!....
grettings from Panama!
 
Did you mean 27 MPG or something else? Do you have manual transmission?
Do you hand calculate your MPG or just look at the gage? The gage is not really accurate, it is best to hand calculate based on at least 2 full tanks and try to fill at the same station (or calculate over more fill-ups to compensate).

27 MPG is on the low side for your vehicle, but is reasonable if you do mostly in-town and/or short trips. If your trips include mostly long stretches of 60~50 MPH, then perhaps something is wrong.
In my experience, fuel economy did not change at all. If I take a highway mostly trip, even when mountains are included, my MPG improves ~2 MPGs over my daily commute, which includes stop-and-go traffic.
 
We just hit 7k in our 2013 AWD and my wife is getting 31-32 all city/country road driving. It was consistently around 27-28 and after hit 6k it just shot up. Im loving it.
 
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We just hit 7k in our 2013 AWD and my wife is getting 31-32 all city/country road driving. It was consistently around 27-28 and after hit 6k it just shot up. Im loving it.

Did the increase in MPG coincide with the end of your N.E. winter? I know my MPG is better than ever now that summer is in full force and I am no longer making regular trips up the ski mountain through slush, sleet, etc. (even though the warm sunny weather requires A/C). You can see my MPG history by clicking my fuelly.com banner. Currently the 9,600 mile lifetime average is 32.0 mpg, way better than the EPA estimated average of only 28 mpg. My last two tanks were 37.5 mpg and 34.2 mpg. It makes me wonder how much better it would be had I opted for 2WD instead of AWD.

I think I smile more when I drive knowing I don't need to dump so much money in my tank just to do the things I want to do.
 
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Did the increase in MPG coincide with the end of your N.E. winter? I know my MPG is better than ever now that summer is in full force and I am no longer making regular trips up the ski mountain through slush, sleet, etc. (even though the warm sunny weather requires A/C). You can see my MPG history by clicking my fuelly.com banner. Currently the 9,600 mile lifetime average is 32.0 mpg, way better than the EPA estimated average of only 28 mpg. My last two tanks were 37.5 mpg and 34.2 mpg. It makes me wonder how much better it would be had I opted for 2WD instead of AWD.

I think I smile more when I drive knowing I don't need to dump so much money in my tank just to do the things I want to do.

Well that is very possible but our winter this year was so mild. Im just thrilled to be reporting these sorts of numbers.
 
I'm impressed with everyone's MPG stats. I'm getting an average of 10.4 L / 100km, which works around 22.5 mpg (pretty crappy) 90% city / 10% hwy, but at the same time I only have around 700km to the engine, and haven't passed the break in period yet. I'm hoping to see better MPG's after more fill ups. Currently only at 2 fill ups, and I tend to fill up when there's 1/4 tank of gas left.
 
I'm getting an average of 10.4 L / 100km, which works around 22.5 mpg (pretty crappy) 90% city / 10% hwy, but at the same time I only have around 700km to the engine, and haven't passed the break in period yet. I'm hoping to see better MPG's after more fill ups. Currently only at 2 fill ups, and I tend to fill up when there's 1/4 tank of gas left.

It'll get better as the engine wears in but you're doing 90% city driving so the extra fuel consumption of the 2.5L will make itself more apparent than if you were doing mostly freeway driving. The 2.0L really shines in city driving mpg, more so than the difference in the 2.0 vs. 2.5 EPA estimates indicate. But your's will improve with break-in. I also suspect the break-in oil is slightly different formula than what is otherwise available and is not quite as slippery. So it should improve a little after the first oil change (I recommend the Moly 0-20).

I am a big fan of wearing in engines by using them moderately hard. Which is best done on faster roads and in the mountains. Opening the throttle up and letting the engine spin wears everything in nice and smoothly. Rings and valves will seal better and carbon will be kept to a minimum. No need to floor it or go all the way to redline but 3/4 of the way there will help everything seal tight and stay nice and clean. Gotta get that puppy a little hot to wear it in properly. My mileage is good precisely because I don't baby it when I need to accelerate and I never hesitate to run it hard once in a while to keep it clean.
 
It'll get better as the engine wears in but you're doing 90% city driving so the extra fuel consumption of the 2.5L will make itself more apparent than if you were doing mostly freeway driving. The 2.0L really shines in city driving mpg, more so than the difference in the 2.0 vs. 2.5 EPA estimates indicate. But your's will improve with break-in. I also suspect the break-in oil is slightly different formula than what is otherwise available and is not quite as slippery. So it should improve a little after the first oil change (I recommend the Moly 0-20).

I am a big fan of wearing in engines by using them moderately hard. Which is best done on faster roads and in the mountains. Opening the throttle up and letting the engine spin wears everything in nice and smoothly. Rings and valves will seal better and carbon will be kept to a minimum. No need to floor it or go all the way to redline but 3/4 of the way there will help everything seal tight and stay nice and clean. Gotta get that puppy a little hot to wear it in properly. My mileage is good precisely because I don't baby it when I need to accelerate and I never hesitate to run it hard once in a while to keep it clean.

Mike is this the same product? https://www.amazon.com/dp/ (commissions earned)

I mentioned a few months ago I had my oil changed at a certain unnamed Mazda dealership. They used Pennzoil not to mention used too much oil. So I took the car to another dealership, which happens to the product in the link above for them to do a correct oil change. Will be going to them fo now on :).

BTW after the break in period I did 2 things. Took a trip to California and back. Then Redline the car at least every other week.
 
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Yep, that's the stuff.

I mentioned a few months ago I had my oil changed at a certain unnamed Mazda dealership. They used Pennzoil not to mention used too much oil. So I took the car to another dealership, which happens to the product in the link above for them to do a correct oil change. Will be going to them fo now on :).

It's too bad mechanics are in so much hurry many can't seem to fill to the proper level. I've had that problem at times at the dealerships of EVERY car brand I've ever owned (except for the ONE oil change I've had done at a Mazda dealership). The CX-5 is my first Mazda. Unfortunately, it's up to individual service techs to get it right so the problem can happen no matter how carefully you select the shop.

In a modern car, too much oil is actually worse than too little. And too much oil can noticeably impact fuel economy as the deeper sump level requires more of the engines lower end to "splash" through the sump oil. Think motor boat plowing through the water.
 

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