Average MPG less than 20mpg, am I alone?

I never made such an implication, that was an assumption on your part, though it was likely based on the wording I used. I'll remove the ignore comment, that was unnecessary. I'll leave the exchange up for context, but will remove myself from the conversation.

As a moderator I try to be less biased in my posts, but I often post here as a member with my own opinions too. Sometimes I cross lines and I apologize for that. But that is a me problem, not a moderator problem.
I didnt even see that you were a moderator - and thought we were making some good points , theres always more than one way to see things- Being able to disagree and not take any issue or subject down a path which deviates into the personal area is a sign of maturity , and thus good debating supported by data helps everyone gather more information and draw their own conclusions--- Kinda like a fair fight ..if you will , Honor among men - This is all good - so no hard feelings here - keep up the good work - thanks for helping run the forum- Why should you ever preclude yourself from debating your opinions or ideas ?
 
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Did you ever calculate the gallons and miles yourself? Maybe your readout was off. It's not normal for these cars to be that low. My average after 3 years of ownership of my 2020 FWD Touring (NA with cylinder deactivation) was 26.5 mpg.
Did YOU ever do the calculations to disprove this theory? Seems like the onus is always on the people who say higher octanes give better gas mileage but the same naysayers always pull out the 1 graph from Mazda and point and screech "SEE, SEE SEE, MAZDA SAYS 91 OCTANE DOESN'T DO ANYTHING!". My total Kms per tank says different, how my motor runs says different, the acceleration on the highway says different. I by no means am saying that you'll get 10hp gains by using 91 octane, but the gains are noticeable.

I stand with GTXT23! Make 91 Octane Great Again!
 
Did YOU ever do the calculations to disprove this theory? Seems like the onus is always on the people who say higher octanes give better gas mileage but the same naysayers always pull out the 1 graph from Mazda and point and screech "SEE, SEE SEE, MAZDA SAYS 91 OCTANE DOESN'T DO ANYTHING!". My total Kms per tank says different, how my motor runs says different, the acceleration on the highway says different. I by no means am saying that you'll get 10hp gains by using 91 octane, but the gains are noticeable.

I stand with GTXT23! Make 91 Octane Great Again!
I believe you stated that the 91 you use has no ethanol. Is that correct? If so, that's the reason you see better fuel economy, but it comes at a co$t. You're also not running the turbo, so you're correct that there's no HP benefit. It's your money, so spend it as you wish! 💸
 
so you're correct that there's no HP benefit. It's your money, so spend it as you wish! 💸
Am I correct? Let me play your game. Have you Dyno'd a CX-5 with and without 91 octane? Until then you have no verifiable data. Wait, you're going to point to the 1 graph from Mazda and screech "SEE, SEE, SEE, MAZDA SAYS NO HP BENEFIT!".

The point is that no one on this board has any real data showing that 91 octane does not provide any benefit or HP gains.
 
Am I correct? Let me play your game. Have you Dyno'd a CX-5 with and without 91 octane? Until then you have no verifiable data. Wait, you're going to point to the 1 graph from Mazda and screech "SEE, SEE, SEE, MAZDA SAYS NO HP BENEFIT!".

The point is that no one on this board has any real data showing that 91 octane does not provide any benefit or HP gains.
The point is that no one on this board has any real data showing that 91 octane does provide any benefit or HP gains.
(speaking of NA motors)
 
The point is that no one on this board has any real data showing that 91 octane does not provide any benefit or HP gains.
Including YOU. :)

Even if you gained 50 HP, you would still be driving a slow top heavy SUV. I'll bet you've also added a CAI. LOL
 
2019 CX-5 Signature Turbo, always use Costco premium 92 octane.

As title says, I'm only getting 18-19 mpg average. I tried to get some decent mileage, intentionally driving like an old man. Well, I'm an old man but it's just too far below the EPA rating. I usually drive 5-10 mile distance on surface road, in small city not much of traffic, occasional freeway driving to 25 miles or so. I expect more than 20 mpg or close to the EPA city rating. The CX-5 has 15,500 miles on it, am I still in break-in period? No other complaints. Oh, once drove 130 mile one way, I got just under 27 mpg on that trip.
Getting 16.4 mpg in 2.5NA. Has 11,800 miles. Mostly city driving in Philly suburbs. I use 93 octane from Costco. The max i peaked on the highway was 31.8 mpg.
 
The point is that no one on this board has any real data showing that 91 octane does provide any benefit or HP gains.
(speaking of NA motors)
That's my whole point. It's a stupid argument. But to lose your mind about people using 91 octane is such a silly thing. If people like it, then let them use it, but to insinuate that people are stupid for using it is just divisive.
 
I do believe engines in today's vehicles may take some advantage to higher than recommended/required minimum octane, but any increase in MPG (topic of this thread) will not offset the increased cost unless something else is wrong with the engine. My detailed MPG tracking has shown no MPG difference between 87 and 93 octane in my turbocharged daily drivers. Both of them specify engine is designed to operate with a minimum of 87 octane and 91+ will offer best performance.

- so if you read the caveat below the 87 rec, it states that fuel below 87 can cause knocking and potentially serious engine damage - so why " walk the line "
at the edge of the damage zone ? What if the fuel has somehow been processed or is in a condition of being 86.9-or lower ? ( an example )- then you are risking damage ....correct ? -- forget performance or gas mileage ..staying on point ...or the " edge " of point -- Why not go 89 and remove that risk --if you think 91-93 is not warranted ?
86.9 octane is not going to cause any more/less damage than 87-93 octane would. From an engineering perspective, I would argue there's some safety factor built into the minimum recommended/required fuel. If engines were designed on the ragged edge like that, failures would be more common.

Almost every owners manual has the disclaimer about lower octane and damage. It's a CYA for the manufacturer.
 
Back to the original topic, I am surprised that there is such a variance reported in mileage here. I get that a turbo will get a bit less mpg, but 16mpg in a 2.5NA? There must be a vast difference in driving styles and conditions to account for such a wide range of mileage figures.
 
I get 16 if I sit and warm the car up for 5 minutes and drive 1 mile to the store. If it's already warmed up, I get 25-27 same trip.
Something isn't right.
 
I get 16 if I sit and warm the car up for 5 minutes and drive 1 mile to the store. If it's already warmed up, I get 25-27 same trip.
Something isn't right.
Letting a car idle (fast idle part of that time if it is cold outside) for 5 minutes will have a significantly negative impact on mpg.
 
Did YOU ever do the calculations to disprove this theory? Seems like the onus is always on the people who say higher octanes give better gas mileage but the same naysayers always pull out the 1 graph from Mazda and point and screech "SEE, SEE SEE, MAZDA SAYS 91 OCTANE DOESN'T DO ANYTHING!". My total Kms per tank says different, how my motor runs says different, the acceleration on the highway says different. I by no means am saying that you'll get 10hp gains by using 91 octane, but the gains are noticeable.

I stand with GTXT23! Make 91 Octane Great Again!
Are you quoting the right person? Not sure why the hostile tone. I never argued that 91 was useless.
 
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Cold weather (-15F to -5 F) has brought this tank average to 18.5 so far. I don’t remote start, and over the last few weeks my engine hasn’t been able to reach temp in 25 minutes of driving with the fan speed on low. So bad MPG’s of course follow as the engine is running rich trying to warm up. Now that the temp is back up to 30, I took a 15 minute drive and got 30.8 MPG. Watching my car on my OBD reader has been interesting. Sometimes the coolant light is off by the time the engine oil is 60 F, sometimes not til it’s 120 F. But milder weather definitely seems to allow these engines to get up to temp MUCH faster, and of course burn fuel as they should.
 
I live in Montana where it had been minus 25F or colder for about 10 days in a row and my wife drives the car 12 miles one way to work. Car sits in the garage when at home and outside when she is at work and mpg went down to 26.5mph on the last tankful my computer always reads slightly less than actual hand figured mpg ie miles driven divided by gas put in.
 
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