Just Bought a 2017 GT AWD - Love it but why such bad gas mileage?

I have a 2016 cx9 sig...nearing 12k miles. Great car ...but as someone pointed out earlier ...the mileage is poor , I am getting 17-18 mpg in semi-urban areas. Brought it up with my dealer ....they are insisting that it is solely based on the driving habits. Reading the posts here appears I should be getting much better mileage ...any suggestions on the course of action I should take will be highly appreciated.
 
I see that most of us are dealing with the same poor mpg(lol2) I too am only averaging 17mpg 75/25, city/highway. Just hit 3k miles on the odo. The only time I'm getting what they are advertising is 23+ mpg on the highway. I tried everything from driving like a old lady to different gas, same result= bad mpg. I'm hoping with what everyone is saying that the car just needs to break in first... I'll post up if that day ever comes.
 
Hey all,
After countless hours of research, I purchased a 2017 CX-9 GT AWD in Machine Grey this past Saturday. I really love the car, it's luxurious and has so many features. One question I have right now is about the gas mileage.

Mike


Hello Mike,

You are my first post!

The new Kodo CX-9 is deceptive in several different and appealing ways. You get a level of performance in a legit seven passenger "Cross-Over" that seats like a mid-size luxury SUV, yet that has "sports car-like" agility to a certain degree. It is deceptive that way for sure. No doubt, it is an SUV. It just doesn't feel like one when you decide to driving like a low end sports car. It has several different personalities depending on what you do with the accelerator pedal.

Regarding the fuel Econ. You would have to take note of the fact that his vehicle is in the 4,000+lb curb weight category. Yet, at times I am almost reminded of my old 1986 RX-7 GSL-SE (not quite, but not far away either).

I just purchased mine (2017 Signature) one month ago after comparing it to the top end Pilot, MDX, Highlander, QX60, QX70 and XC90. That's some pretty stiff competition inside a fairly wide/deep price range all the way up to the XC90. I was more than willing to pay for either.

At the end of the day, I kept coming back to the Signature. Not because it was the absolute best SUV in any one category among the competition, but because it scored better in all categories within my system of scoring among the competition and MPG was one of those areas. I had a very wide range of qualifications and the Signature had the most well rounded score. That was pretty impressive to me, so I bought it.

At over 4,000lbs, having a turbo charger and purpose built engine/transmission design that intentionally places most of the torque and power down low on the RPM band, you will by definition burn a bit more fuel in normal driving -if- as you say, you put your foot in it as a normal habit. It is a 4-cylinder engine and it has to get that mass of the vehicle moving down range somehow and it will require energy production to accomplish that even in normal driving. I suspect this is where the fuel economy of the new Kodo CX-9 might suffer a bit.

However, the other well thought out benefits of the power delivery design, I thought out weigh the slight loss of MPG under normal driving conditions - if you have a normally heavy foot. Namely, the output realized lower on the RPM band and the usability of that power in normal driving and during those "special moments" when you simply want to get out from behind slower traffic with a little quickness. In order to get that level of responsiveness out of the 4-banger, a little fuel Econ had to be sacrificed. I'm sure that realization was not lost on Mazda design engineers and I think they kept things within an envelope of "acceptable sacrifice" that makes sense.

Having said all of that, I'm easily seeing 20-21 MPG with normal mixed driving and that comes from a guy who purchased the new C5 Corvette (MN6 coupe with blue removable top) and drove it like I stole it nearly every day. So, my foot is naturally heavy. I believe I could get as much as 22-23 MPG out of my Signature, but then I'd end up driving like my Wife, very slow out of the gate and that's just not my style. (headbang)

I could have easily gone with the XC-90 Inscription and almost did exactly that. However, according to my analysis, by purchasing the CX-9 Signature, I got 80% of the XC-90 Inscription for about 50% of the total cost! I just did not see paying upwards of $80K (the way I wanted the XC-90) for 20% more SUV.

Now, I'm not saying the Volvo XC-90 Inscription is somehow not superior (in almost every way) to the Mazda CX-9 Signature. Indeed, it is. I'm simply saying that I did not see the value of paying nearly $30K-$40K extra for just 20% more vehicle at the end of the day. The very first qualifier was IIHS Safe Rating. In that very first qualifier round, the XC-90 and the CX-9 were at the top of their class.

The other vehicle that finished in the final three was the Acura MDX Advanced. However, I just felt that as a daily driver that its SH-AWD was a bit too intrusive and in the foreground for me personally - whereas Mazda's i-ACTIV AWD system has the feeling of sitting more in the background of the overall driving experience.

Your MPG numbers seem a bit off to me, even for someone with a slightly heavy foot. I'd take it back to the dealer's maintenance department while still under power-train warranty and have them focus on specific fuel consumption.
 
I have a 2016 cx9 sig...nearing 12k miles. Great car ...but as someone pointed out earlier ...the mileage is poor , I am getting 17-18 mpg in semi-urban areas. Brought it up with my dealer ....they are insisting that it is solely based on the driving habits. Reading the posts here appears I should be getting much better mileage ...any suggestions on the course of action I should take will be highly appreciated.

I see that most of us are dealing with the same poor mpg(lol2) I too am only averaging 17mpg 75/25, city/highway. Just hit 3k miles on the odo. The only time I'm getting what they are advertising is 23+ mpg on the highway. I tried everything from driving like a old lady to different gas, same result= bad mpg. I'm hoping with what everyone is saying that the car just needs to break in first... I'll post up if that day ever comes.



Guys, I'm seeing 20-21 as posted above and that's with spurts up to 108 on the open highway with nothing around but me, the road and bugs. Its a daily driver/commuter with a few long drives on the weekends. A 2017 Signature just over 1 month old now. No mechanical issues to report.

Check your fuel supplier. Not all Unleaded Fuel sold in the U.S. is equal and not all engine designs will burn all unleaded fuels as efficiently. I remember an old Texaco station where I used to refuel my C5. The V8 LS1 simply had more pop and better fuel Econ running on that fuel source than the Chevron across the street. I distinctly remember not being the only Corvette owner in town who said that. A couple Viper owners were saying the same thing. There was something about either that fuel or the LS1 or both that caused them to like each other very much. It was noticeably snappier and lasted longer that's for sure.
 
New 2017 CX 9 GT, just took it on a 1,000 mile trip. On my trip north to Santa Cruz through tough LA traffic and cruising at 75 mph I got 25 mpg. On the way home I eased up and cruised at 65 and I got 29.5. At one point I was over 30.5 mpg, but again LA freeway traffic lowered my avg. Very happy with the car snd mileage.
 
My '18 has just a tick over 1k miles on the Odo, but in mixed driving, I'm averaging 25.6 MPG (per the computer, I haven't measured at the pump). Most of my driving is either suburban or freeway.
 
While I absolutely loved the look of the Signature interior, I decided not to buy it because it only comes with AWD, and after reading Consumer Reports on AWD, I wanted a CX-9 without AWD. (I seldom venture outside of Flat Florida anyway).

My beautiful 2018 FWD GT is still on its initial tank, A is showing 25.3mpg, B is showing 25.4mpg. Most of my driving is "in town", 35-45mph, and I drive "light-footed", and never in "sport" mode. (My 2014 FWD CX-9 settled on 19.5 mpg over 10k miles or so of the same type of driving) - so I am very pleased with this gas mileage.
 
CX-5 Touring owner here. I hit 29 on the tank and individual trips in morning are about 30+ with many 34 / 35 runs.
Mazda's are setup to give you good mpg numbers in around town speeds. My CX5 is most efficient at 32 mph and 47 mph (when it upshifts to 5th and 6th under light loads). At times driving 32 on certain narrow roads my instant mpg number never drops from 40 mpg. MPG goes to pits at 70+ mph, also due to the nature of the tranny I drive with my foot off the pedals many times as it downshifts and brakes a bit for me.

CX5 with cylinder deactivation would add 1 or 2 mpg. If you are in tune with your machine 2 mpg above city EPA estimates are doable unless you drive 70 mph + most of the time.

Also - CX5 has had issues with EPB not releasing fully this hurts mpg and kills the rear pads sooner - there have been TSB's for this specific issue. Not sure if this is a pain point for CX-9. One way to check is : In an empty lot engage Parking brake and shift to D, give light throttle - the car should not pull left or right and EPB should release.


My best morning commute 30 mins:
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2018 GT here, and just breaking it in at around 400 miles. I am definitely heavy footed as I like the acceleration and have been driving only local - that said, gas mileage is horrific at 11-12mpg from the on board computer! Thats pretty ridiculous and way worse than my 3.6L v6 2009 Mazda 6 where I at least got 17-18mpg. What do you guys think, should I be taking it to the dealer to have it checked out?
 
2018 GT here, and just breaking it in at around 400 miles. I am definitely heavy footed as I like the acceleration and have been driving only local - that said, gas mileage is horrific at 11-12mpg
As painful and as frustrating as it can be when breaking in a new car, taking it easy the first 1,000 miles or so is the recommended way to go.
400 initial miles with a heavy foot says it all. This is not the way to break in a new engine.
Gas mileage will be poorer to begin with when it's new, and driving it from day one like you're on a race track is about the worst thing you can do, for more reasons than just bad gas mileage.
Take it easy.
 
Can you elaborate a little more on on where you are getting 11-12MPG? I assume this has to be city...if you are saying highway I'd be checking with dealer. That is what I get towing a 5K lb load behind my GX with a 4.6L V8.
 
As painful and as frustrating as it can be when breaking in a new car, taking it easy the first 1,000 miles or so is the recommended way to go.
400 initial miles with a heavy foot says it all. This is not the way to break in a new engine.
Gas mileage will be poorer to begin with when it's new, and driving it from day one like you're on a race track is about the worst thing you can do, for more reasons than just bad gas mileage.
Take it easy.
https://en.m.wikipedia.org/wiki/Break-in_(mechanical_run-in)

As even this says it is no longer a thing to need to break an engine in.

The worst thing you can do is even load / cruise control on the level for the first miles. With the design of this engine it is not going to be pounded to 6k rpm at each red light. The transmission primarily keeps it on the 500-4500 range.

Seems like the techniquique used is appropriate

Here is the view from Mazda

http://www.mazdaoflodi.com/blog/do-you-have-to-break-in-a-new-car/
 
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Can you elaborate a little more on on where you are getting 11-12MPG? I assume this has to be city...if you are saying highway I'd be checking with dealer. That is what I get towing a 5K lb load behind my GX with a 4.6L V8.

Definitely more city, not highway. I live in Northern VA and traffic is heavy even on highways so its mostly a stop and go driving.

To others points, I am not abusing the car and constantly redilining or flooring the pedal. I have still floored the gas a few times but thats not it - I drove a bit with the gas mileage meter on the info display and it was near the very bottom under any kind of acceleration, lighter or heavier. So its the stop and go driving, and if that meter is correct it would imply I would get even worse mpg under lighter acceleration (as it would take longer :).
 
https://en.m.wikipedia.org/wiki/Break-in_(mechanical_run-in)

As even this says it is no longer a thing to need to break an engine in.

The worst thing you can do is even load / cruise control on the level for the first miles. With the design of this engine it is not going to be pounded to 6k rpm at each red light. The transmission primarily keeps it on the 500-4500 range.

Seems like the techniquique used is appropriate

Here is the view from Mazda

http://www.mazdaoflodi.com/blog/do-you-have-to-break-in-a-new-car/

Buzzman12 and HobokenSkier, thanks for you replies! I had read similar things that the break in of old isnt needed anymore, though on some level that still feels weird, so I am definitely not pushing as hard as I would normally. I will try to do some more sanguine driving and see if that makes a difference, but the gap to the 17-18+ mpg I saw others posting just seems too big...

I hope the low mpg is just because the car is breaking in, would be great to hear from others breaking in their 2018s.
 
Buzzman12 and HobokenSkier, thanks for you replies! I had read similar things that the break in of old isnt needed anymore, though on some level that still feels weird, so I am definitely not pushing as hard as I would normally. I will try to do some more sanguine driving and see if that makes a difference, but the gap to the 17-18+ mpg I saw others posting just seems too big...

I hope the low mpg is just because the car is breaking in, would be great to hear from others breaking in their 2018s.

I've got about 900 miles on the AWD Signature, 80% city / 20% hwy.
According to the computer, I average 20-21mpg. That's using non-ethanol fuel.

When posting fuel numbers, it would be nice to know if we're talikng FWD or AWD and what type of fuel.
 
Im not disappointed in my signature. It really does depend on how you drive the vehicle.

When I drive it like I stole it, I get somewhere down between 17 to 18 mpg.

When I drive it like I didnt steal it, I see a minimum of 20 mpg no matter where I take it, and I get as high as 22 to 23 MPG doing both combined highway and street driving - normal commutes.

I think on a long continuous drive of 300+ miles or so, I could probably get this thing close to 27 MPG.

(This message was dictated using iPhone voice to text!)
 
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