Horrible gas mileage in brand new CX-5

[Mike2000z28]

Hi guys, I recently leased a brand new 2025 cx5 GT with 64km on the clock. I got it with a full tank of gas and it has around 204km on it now at pretty much a half of tank.

I literally have a 4km commute to work pure city stop and go, and im driving like a grandmom because I still can't believe the mileage. Im getting around 15L/100 with granny driving.

Keep in mind this is warmer temps and I live in Canada. I used to have a 2008 cx9 GT Awd that got similar mileage but that was expected for that truck. If it doesn't change im going to have to give it back. I was expecting 4 cylinder gas mileage of mid 20smpg, not 16mpg.

Has anyone else this issue with a fresh brand new cx5 with the 2.5 NA?

 

[sm1ke]

4km commute to work pure city stop and go

I could see this mileage being possible with short commutes and city driving. If you took the car for a 5-10 minute drive down the highway, your mileage for that drive would be much better.

 

[Mazdiod2]

204km on it now at pretty much a half of tank.

I always like to take a new car on some longer cruises, if possible. Especially on the highway for an hour or two.

 

[sm1ke]

I could see this mileage being possible with short commutes and city driving. If you took the car for a 5-10 minute drive down the highway, your mileage for that drive would be much better.

I should note, though - a highway drive may not be a good idea with such a new car. Since the car is still in it's "break-in" period, you don't want to be cruising along at the same engine RPM for an extended period of time. Usually this means no road trips or long drives. I think a 5-10 min drive would be fine, but to be on the safe side, you'd want to vary the engine RPMs often, and let the engine get up to normal operating temps instead of driving it "cold" often, based on what the owner's manual recommends for new cars.

 

[Mike2000z28]

That's the issue as well as the car doesn't get to operating temp I think. What should the thermostat reading be at full operating temp? 100 degrees celsius?

 

[N7turbo]

Cold engine = below rated mileage

Stop and go = very inefficient

I think you would benefit from a hybrid.

 

[sm1ke]

That's the issue as well as the car doesn't get to operating temp I think. What should the thermostat reading be at full operating temp? 100 degrees celsius?

Normal operating temp is about 90c. Right in the middle of the temp gauge.

 

[Mike2000z28]

Cold engine = below rated mileage

Stop and go = very inefficient

I think you would benefit from a hybrid.

Yeah, but cmon city mileage is city mileage. It's short trips and stop and go. 15l per 100km is to much of a difference. My cx9 was older and got the advertised mileage for the most part.

 

[Mazdiod2]

If you drive carefully (like you say you do) and they haven't added any new construction or delays on your route that cause excessive idling you should easily expect same or better than your old CX9.

I guess even a newer, low mileage car can have some basic issues that could cause this.

Have you checked things over, like the air pressure in the tires, etc? You would think the dealer set the air pressure but maybe not.

 

[sm1ke]

Checking the tire pressure is a good idea, but usually if the car isn't PDI'd correctly at the dealership, the tires would be overinflated, which would affect ride quality but also improve fuel economy. Underinflated tires decrease fuel economy.

@Mike2000z28 you should also keep in mind:

• this is your first tank and you're only halfway through it
• the fuel economy readout is an estimation/approximation based on the current "trip" setting
• the car's ECU and transmission are still learning and adapting to your driving habits

It would be more accurate to manually calculate your mileage after your next few fill ups, then take an average of each tank to determine your actual fuel economy.

There's no need to drive it like a grandma, just drive it how you'd normally drive it and reassess after a couple of tanks of gas. Accelerate normally so you go through the gears to get to your cruising speed sooner. I wonder if "driving it like a grandma" means the car spends more time at a higher RPM because you're accelerating just enough to get to speed, but not enough for the transmission to shift to a higher gear? Maybe the A/C is blasting constantly? Lots of stuff to consider.

 

[leeharvey418]

400 km is pretty close to what I get on an ‘indicated’ tank in mixed driving. My CX-5 leaves ~11 L of buffer when the low fuel light comes on.

 

[cz5gt]

Yeah, but cmon city mileage is city mileage. It's short trips and stop and go. 15l per 100km is to much of a difference. My cx9 was older and got the advertised mileage for the most part.

Unfortunately your are right where it should be for 2.5 miles stop/go drive. The car can never reach operating temp.

for such short commutes better is hybrid or best is EV

 

[erhayes]

Before accepting that mileage, I would fill your gas tank, record the mileage and when approaching the 1/4 tank level, do a hand calculation to get a true value of miles/gallon.

 

[SparkYellow]

Before accepting that mileage, I would fill your gas tank, record the mileage and when approaching the 1/4 tank level, do a hand calculation to get a true value of miles/gallon.

When you do that, what is the difference between the manual calculation and computer mpg? I assume the true value is lower?

 

[leeharvey418]

When you do that, what is the difference between the manual calculation and computer mpg? I assume the true value is lower?

I've seen mine go either way.

 

[SparkYellow]

I've seen mine go either way.

The computer shows my mpg as much higher than the EPA figures. I wonder if I should take 3 or 5 off...

 

[N7turbo]

The computer shows my mpg as much higher than the EPA figures. I wonder if I should take 3 or 5 off...

Compare it to your actual calculation, not the EPA figures.

 

[Mazdiod2]

When you do that, what is the difference between the manual calculation and computer mpg? I assume the true value is lower?

The times I have checked the computer MPG it was lower than the actual calculated, but I've only done the calculations a few times. I think it was 2-3mpg difference.

 

[2020 CX5 Ow]

Hi guys, I recently leased a brand new 2025 cx5 GT with 64km on the clock. I got it with a full tank of gas and it has around 204km on it now at pretty much a half of tank.

I literally have a 4km commute to work pure city stop and go, and im driving like a grandmom because I still can't believe the mileage. Im getting around 15L/100 with granny driving.

Keep in mind this is warmer temps and I live in Canada. I used to have a 2008 cx9 GT Awd that got similar mileage but that was expected for that truck. If it doesn't change im going to have to give it back. I was expecting 4 cylinder gas mileage of mid 20smpg, not 16mpg.

Has anyone else this issue with a fresh brand new cx5 with the 2.5 NA?

I also have the GT and yes, the city fuel economy is not the greatest that's for sure...that dang all-wheel drive is to blame for it, along with being only 6 speed and naturally aspirated.

I drive the 401 90% of my kms and I notice when I put on my winter tires (17 inch vs. 19) I get around 8% better fuel economy. On the highway I'm averaging 8.4 with the 19 inch rims/tires, 7.8 with the 17 inch rims.

C'est la vie.

 

[SimpleCanuck]

I also have the GT and yes, the city fuel economy is not the greatest that's for sure...that dang all-wheel drive is to blame for it, along with being only 6 speed and naturally aspirated.

I drive the 401 90% of my kms and I notice when I put on my winter tires (17 inch vs. 19) I get around 8% better fuel economy. On the highway I'm averaging 8.4 with the 19 inch rims/tires, 7.8 with the 17 inch rims.

C'est la vie.

I would think that the heavier weight of your 19" rims is decreasing your fuel economy during the other 3 seasons. My '22 GS has 17" rims for both 3-season and winter tires, and I routinely get similar fuel economy as yours with winter rims when I drive on expressways.