Average MPG less than 20mpg, am I alone?

I have a cx-5 2.5l turbo with over 44k miles and regularly see 19 mpg in mixed driving. I first tried 4 tanks full of 93 with no change in mpg. Then switched to regular gas with same results (at least 4 tanks).

I bought the CRC GDI Turbo spray. Had a friend in driver seat and keep throttle at ~2k rpm’s while I sprayed it (disconnect rubber tube from the air box and followed directions on bottle spraying away from MAF sensor). Afterward I noticed my MPG’s went into the low 20’s and increased throttle response with same driving habits.

I don’t work for CRC and I used the car’s own in dash mpg gauge to compare before and after.

I plan on replacing the OEM air filter with a K&N to see if it would help (Even though the OEM is still clean).

Finally, as others mentioned if you do short drives (under 15 minutes) it will hurt the cars mpg’s. As the car is not fully warmed up no matter what the dummy thermostat says in the car’s display gauge. Also, this turbo spools really quick so best bet is to ensure the car is shifting below 2.5k rpm’s. And I tried with and without traction control and made no difference.
I would try this one first. They say you clean your k&n filter and over oil it it can eventually mess up something in your car. I have been impressed with this you can clean it and it’s a lot cheaper.
 

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Tribe&TrueRacin

Member
Banned
:
Mazda
I would try this one first. They say you clean your k&n filter and over oil it it can eventually mess up something in your car. I have been impressed with this you can clean it and it’s a lot cheaper.
In a few that owners of K&N filters did not read the simple HOW TO CLEAN instruction caused a MYTH that K&N will cause DTC (diagnostic Trouble Codes) which was due directly to over oily the filter.
 

acidbug

ZoomZoom CX-5
Contributor
:
‘19 CX-5 GTR
In a few that owners of K&N filters did not read the simple HOW TO CLEAN instruction caused a MYTH that K&N will cause DTC (diagnostic Trouble Codes) which was due directly to over oily the filter.
100% truth. I worked at a mechanic shop when I purchased my first Mazda and saw some cars (not just Mazdas) with MAF soaked in the oil cleaner. Sometimes MAF cleaner would work, others required replacement MAF’s.

After oiling/cleaning the K&N Air filter I would let it sit out on a rag in the sun. Occasionally swinging the filter with the rag over it to help push out the extra oil). Alternatively, To speed it up I would used air compressor.

The problem is only need a little of the oil if you’re properly maintaining it and give it some time to dry up (~1 hour). And yes you should clean/oil it more frequently if you lived near the beach or desert or in areas that do heavy salting of the roads(due to heavy snow/ice roads).
 
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Tribe&TrueRacin

Member
Banned
:
Mazda
100% truth. I worked at a mechanic shop when I purchased my first Mazda and saw some cars (not just Mazdas) with MAF soaked in the oil cleaner. Sometimes MAF cleaner would work, others required replacement MAF’s.

After oiling/cleaning the K&N Air filter I would let it sit out on a rag in the sun. Occasionally swinging the filter with the rag over it to help push out the extra oil). Alternatively, To speed it up I would used air compressor.

The problem is only need a little of the oil if you’re properly maintaining it and give it some time to dry up (~1 hour). And yes you should clean/oil it more frequently if you lived near the beach or desert or in areas that do heavy salting of the roads(due to heavy snow/ice roads).
(y)(y)(y)(y)(y):cool:
 
Hey guys, just new here and got my 22 Signature like 2 weeks back. It's got 155KM and average MPG from the dash is 16.4L/100KM. This is my first Mazda and first turbo charged vehicle. I've been reading some posts and my average is just too low. I've been doing 100% city driving; 6KM going to work and 6KM going back home. My question is, would the average improve when I get more mileage from the vehicle? Also, I know for a fact that the trip is too short for the engine to warm up, thus the poor MPG. I was hoping to get at least a 14L/100KM. Also, I don't have a heavy foot.
 
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2021 CX-9 Sig
:
2021 CX-5 GT
Hey guys, just new here and got my 22 Signature like 2 weeks back. It's got 155KM and average MPG from the dash is 16.4L/100KM. This is my first Mazda and first turbo charged vehicle. I've been reading some posts and my average is just too low. I've been doing 100% city driving; 6KM going to work and 6KM going back home. My question is, would the average improve when I get more mileage from the vehicle? Also, I know for a fact that the trip is too short for the engine to warm up, thus the poor MPG. I was hoping to get at least a 14L/100KM. Also, I don't have a heavy foot.

All vehicles have poor mileage in the beginning - especially in the first 3000 miles. Improves dramatically after the first oil change. 155km is nothing.
 
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Southwest Ohio
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'19 CX-5 diesel
Have you reset the dash readout? If not, that likely includes whatever idle time, yard transfers etc before you got your hands on it.

So many variables about driving conditions though. You have a very short drive and even in the best of conditions (no traffic, no stops) with that short of a drive your numbers are going to show low efficiency . For your short drive, are you in stop/go traffic? Waiting on traffic lights? Waiting in the drive-thru for a morning beverage or doughnut?

I imagine you had a car before the Mazda and drove the same route/conditions ... How did it compare to the "book numbers"?
 
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18 Mazda CX5 AW
My fuel dash readout is pretty accurate. However that doesn't mean yours isn't malfunction. Try a new fill-up and reset the gauge. Run a full tank through and manually calculate your litres/km and compare to your dash readout.

Like hiflyer notes above, alot of factors affect efficiency
Also, are you hauling alot of cargo in your hatch trunk ? do you run the AC alot? Maybe your heavier on the gas peddle than you think?
Try using cruise control and see what your litres/km is. Lastly idling the vehicle whether in driveway or at stoplights waste alot of gas. Until I had a dash meter I never realized how much it drags your mpg efficiency down. Now I start the car and go. I also drive slower to try and time the lights green.

If you're still getting low fuel efficiency after all that then you may want to take back to the dealer.

My 15 year old Ford V6 SUV got 14 to 16 mpg which is similar to yours so that is really low for a brand new 4 pot, even turbo model
 
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Have you reset the dash readout? If not, that likely includes whatever idle time, yard transfers etc before you got your hands on it.

So many variables about driving conditions though. You have a very short drive and even in the best of conditions (no traffic, no stops) with that short of a drive your numbers are going to show low efficiency . For your short drive, are you in stop/go traffic? Waiting on traffic lights? Waiting in the drive-thru for a morning beverage or doughnut?

I imagine you had a car before the Mazda and drove the same route/conditions ... How did it compare to the "book numbers"?
I was excited when I got the vehicle that I wasn't able to check the MPG on the dashboard haha. But it had only 5KM on it when I got if from the dealership and it's got a full tank.

As I live in Montreal, there's a lot of traffic lights along the way, so yeah typically stop and go. My previous vehicle was a 2017 corolla that goes for around 7-8L/100KM city driving also, which I think is pretty good or normal for that kind of vehicle.
 
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My fuel dash readout is pretty accurate. However that doesn't mean yours isn't malfunction. Try a new fill-up and reset the gauge. Run a full tank through and manually calculate your litres/km and compare to your dash readout.

Like hiflyer notes above, alot of factors affect efficiency
Also, are you hauling alot of cargo in your hatch trunk ? do you run the AC alot? Maybe your heavier on the gas peddle than you think?
Try using cruise control and see what your litres/km is. Lastly idling the vehicle whether in driveway or at stoplights waste alot of gas. Until I had a dash meter I never realized how much it drags your mpg efficiency down. Now I start the car and go. I also drive slower to try and time the lights green.

If you're still getting low fuel efficiency after all that then you may want to take back to the dealer.

My 15 year old Ford V6 SUV got 14 to 16 mpg which is similar to yours so that is really low for a brand new 4 pot, even turbo model
I will try to do a full tank and reset the counter and do a manual calculation and compare it on the dash readout.

I don't haul any huge cargo. It's usually myself or my wife and 3 yr old daughter. I run the AC at a low fan setting. I've also tried driving around without the AC but it doesn't change that much. I've read about the idling of the vehicle, and yes I don't do that. I've also read somewhere that throttling a bit aggressively from stop helps with the efficiency as it gets you up to speed much quicker. I've noticed a small difference only; from 16.4L to 16.3L/100KM.

My usual speed around the city is between 30-40KM/hr. I will try to drive it on the highway as soon as I do a full tank and do a dash readout reset. Maybe observing my driving habits also as this is the first SUV I've owned. I might not be as light footed as I think I am haha.

Thanks for the feedback and suggestions guys!
 

acidbug

ZoomZoom CX-5
Contributor
:
‘19 CX-5 GTR
Finally got my K&N filter in the mail. I’ll report back after a few tank fills with my results. Also, I ran a tank with BG44k recently to ensure the injectors, fuel pumps etc were in top condition. Running in sport mode every where I went to get it to clean up the fuel system. I’m the 2nd owner of my Mazda and it wouldn’t surprise me if the previous owner was filling with cheapest gas they could find. The Mazda dealer had no records of oil changes and which hopefully means they were at least getting oil changes at independent shops(my guess is that it was a leased vehicle).

P.s. when I ran the bg44k , I ran the tank down to almost empty. Dumped in the bg44k an filled with premium. Been driving pretty aggressively so I could quickly burn through the tank with the bg44k Additive. Once the K&N filter is in I’ll go back to driving normally to see if there is an improvement in mpg. BTW, we are in the midst of summer so I always use my remote start & have my AC blasting which will slightly reduce mpg.
 
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Finally got my K&N filter in the mail. I’ll report back after a few tank fills with my results. Also, I ran a tank with BG44k recently to ensure the injectors, fuel pumps etc were in top condition. Running in sport mode every where I went to get it to clean up the fuel system. I’m the 2nd owner of my Mazda and it wouldn’t surprise me if the previous owner was filling with cheapest gas they could find. The Mazda dealer had no records of oil changes and which hopefully means they were at least getting oil changes at independent shops(my guess is that it was a leased vehicle).

P.s. when I ran the bg44k , I ran the tank down to almost empty. Dumped in the bg44k an filled with premium. Been driving pretty aggressively so I could quickly burn through the tank with the bg44k Additive. Once the K&N filter is in I’ll go back to driving normally to see if there is an improvement in mpg. BTW, we are in the midst of summer so I always use my remote start & have my AC blasting which will slightly reduce mpg.
Keep us posted….