CX9 horrible feul consumption?!!

clnc

Member
:
CX-9
hello
i want to ask about feul consumption in the 09 GT
ithink mainly its me but like to check
when in kick down computer says 99l/100km and i could see the fuel guage going down
on slow acceleration from 0 get 40l/km
rolling low speeds get 23l/100km
high way get 16l/100km
i use premium unleaded, synth oil,not towing, no AC

i once used the AC but when kicked down warm air came insted of cold

is that normal should i reset the car computer or do something else
 
My driving highway is about 20mpg for a long trip. Short trips may be different.
City is about 15mpg. I am not complain its mileage.
However, I use just regular unleaded as recommended.
 
I got around 14 to 16 in the city. When i went to baltimore i was averaging 24.5 miles per gallon on the highway doing around 70mph.
 
2010 fwd sport:
23MPG Hwy
18.5MPG Suburban streets
Note: When calculating hwy mileage, make sure to average both directions since incline and wind direction can make a big difference. In my case, hwy was 22 in one direction and 24 in the other. The onboard trip computer shows the mileage to be 1-3% better than what it actually is.
 
Use of premium fuel would actually reduce MPG (though very slightly) if your CX9 has no knocking issue.
Premium fuel has less energy density per volume. You pay more, and get less energy per gallon, so to speak.
It only works if your engine is designed for it. i.e. higher compression ratio than the 10.2 which is ratio of CX9's engine.
Higher compression gives more torque, therefore, more horsepower at same RPM. Our CX9 MZI 3.7 is designed for regular unlead. Using premium fuel will not give you
more torque. In fact, less due to less energy density per volume.

On city drive, go easy on the 1st gear. Always try 42mph than 40mph whenever possible or legal
since CX9's tranny shifts to 6th gear at 42mph.
 
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08 AWD GT
14 on a good tank for city, but i'm notoriously lead-footed
22 on highway

ditto here - same car, same mileage, same lead foot. If I wanted 50 mpg I'd have bought a Prius......not! zoom zoom
 
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guys your numbers are great compared to mine
on hard acceleration from zero i literally get 2.35 MPG then it keeps going up to 11mpg
now when i baby the car from stand i get 5.81MPG
all are instantaneousness readings my AVG on info display is 11.87MPG
now mostly its city driving no AC medium traffic
 
guys your numbers are great compared to mine
on hard acceleration from zero i literally get 2.35 MPG then it keeps going up to 11mpg
now when i baby the car from stand i get 5.81MPG
all are instantaneousness readings my AVG on info display is 11.87MPG
now mostly its city driving no AC medium traffic

That is pretty bad but instanteous miles/gallon is very misleading during acceleration as you don't actually accelerate for more than a few hundred yards at time. The average mpg indicator is more reliable and matches my actual gallons pumped within a few tenths of an mpg when I bother to measure it. The worst I get for a tank spent in city with A/C is about 15. Best is about 22-23 with 70mph highway driving. Average mixed is about 17-18 with equal urban/suburban/highway miles.

And I agree with others that using premium fuel is foolish. Someone is listening to oil company marketing hype rather than reading the manual.
 
Have you tried putting it in average MPH as opposed to current? My first 2 weeks I was averaging 16.5 MPG. Now I am up to 17.4. Truck is still less than a month old. The current MPG readings dont tell the whole story.
 
guys your numbers are great compared to mine
on hard acceleration from zero i literally get 2.35 MPG then it keeps going up to 11mpg
now when i baby the car from stand i get 5.81MPG
all are instantaneousness readings my AVG on info display is 11.87MPG
now mostly its city driving no AC medium traffic

The instantaneous mileage readout is not very useful. I get low single digits pretty regularly.

The last time I checked, the average MPG readout was 18.4 MPG. Most of the miles are city. We live in Florida, which is very flat, so that helps.
 
Did a scientific experiment yesterday: i tried all the tricks I know on saving gas: like easy pedal, etc. Just want to see how far I can get.... and here is the result:
New tank of #87 unleaded gas, two adults
30 miles round trip, with 20miles on highway (70mph, mostly on cruise control), and 10miles on suburban (45-50 mph)
some small up and down hills
AC is on, but for heat only(so it's not really on?)
I can get 23.9 MPG average.

The experiment was kind of fun, but I guess I will go back to my normal driving style with 17 MPG in town.(evil)(nana)
 
Stop-n-go is what kills MPG for a heavy vehicle like the CX9.
Short drives do the same impact due to cold engine and CAT converter
(due to emission control, it needs to be heated up quickly. Therefore, engine runs rich.)

Once you can maintain 6th (42mph+) gear smooth sailing, CX9 is very fuel efficient, highway or local suburb.
 
I get a dismal 14 in the city. On the highway on a recent trip (1600 roundtrip w/ NO A/C), I finally manage 18. But was averaging 80mph.

Where's that fellow who claims he can easily get 24mpg w/ no effort at all? Is he gone? Finally got rid of his $36k FWD sport??
 
2010 CX-9 Touring
30 miles, combo street, mostly highway miles daily. drive time between 25 - 33 minutes, little traffic to there, lots of traffic from there. I average between 20 - 24mpg to and 18.8 - 21.5mpg back. I have only added a K&N filter sofar. I will switch to Synthetic oil soon. The worst I got average while putting my foot into is 17 mpg on that trip. If I stay below 2000 rpm, mpg stay above 20, above 2000 it drops below 20mpg.
 
I get a dismal 14 in the city. On the highway on a recent trip (1600 roundtrip w/ NO A/C), I finally manage 18. But was averaging 80mph.

Where's that fellow who claims he can easily get 24mpg w/ no effort at all? Is he gone? Finally got rid of his $36k FWD sport??

Lol, I haven't seen CX9SportOwner on here in a long time. He was kind of a polarizing figure for some. I thought he was really helpful.
 
Hmmm, I am noticing that when it rains or has been raining and the humidity is high, I get a lot better gas mileage than normal. Are any of you noticing this on the CX-9?
 
My wifes 2009 Gt gets 16 mpg city and 20 mpg highway. Its hard not to have a lead foot when the car drives so much like my mazda speed protege.
But i got 30 mpg on a snow board trip (in my MSP)from Charlotte N.C. to Beach mtn. N.C... Who cares how many mpg's it gets gas is cheap.. lol
 
OBTW, I noticed an interesting quirky thing. I filled up the other day and drove around a bit, then decided to top off for the upcoming week, and this time I left the key and the the radio on. When I restarted the car, the miles remaining stayed at 342 miles, even though I had just added 3.4 gallons to the tank to top it off. Seems to me when I did this once before, the miles remaining jumped up as expected to 402 - 409, as I did have the car off and the key out of the ignition, but not this time. The reading has been steadily dropping since the refill as one would expect. However the fuel gauge is reading as it should higher than what I have come to expect in comparison to what I am seeing on the remaining miles? Anyone else have this occur to them? Next time I fill up, I am gonna take the key out and see if the miles remaining resets and climbs appropriately.
 
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