Ive read your "credentials" on the website....but my choice of fuel has never led to any engine service issues in 50+ years of driving, some vehichles kept for 15 plus years, some owned, some leased. NEVER had a major engine or transmission issue, have never even been stranded anywhere. stay ahead of your....normal maintenance stuff.

 

Why is there always the member that is the exception to the general rules/

Ok great that you have never had a problem that you were aware of. And also that you have never been stranded. But every week if not every day on countless forums you would be considered a rare owner not ever having issues with any vehicle in 50+ years. LOL You can tell yourself that all you want! Yet every day on Mazda forum alone and not other forums but I could include them some member has a problem.
Is it there choice of fuel/gasoline well I could say unless I personally worked on their vehcle. Do I get customers that there direct problem is by using a choice of gasoline, hard to say but then people who smoke always want to tell you that they have been smoking for say 50+ years and never had a health issue..... until they do.

Bottom line it your vehicle and you can treat it anyway you like which includes your choice of gas. So Happy Motoring LOL
I suggest to look into the average service shop hourly rate so you are prepared just in case you don't make it to 51+ years of never having a vehcle problem.

 

Yes there are " positives " a 13:1 engine - particularly a miller cycle with absurdly short combustion stroke will have serious issues if predetonation occurs from using low octane fuel -
Mazda states minimum 87 ( for sales and marketing reasons ) -on the NA - any less can do severe engine damage...they state ... - and thus using top tier fuel - high octane to help prevent pre-detonation in HC engines is prefferable .89 min- and I use 91- Why skirt the edge of what even Mazda says causes severe engine damage..below 87 ..which on any batch could occur -I stay in the safe zone 89-93- and notice a difference in performance - I mean in the Turbo 2.5 hp and torque are increased significantly and the CR is lowered to 10:1- to keep the heads from cracking or gaskets blowing out as they max around 17 - so the dyno reveals an increase in hp on the NA as well -
The owners manual states - use high octance 91 when towing - thats on the na - that should tell you all you need to know

 

this is a great response I agree with most everything.

I also like reading that most do not understand or even really know the process of how base gas and the distribution of specific formulas for Shell, Chevron Costco etc… are mixed and then distributed.

I think some would laugh .

I lived near Benicia CA visited the chemical fueling distribution centers many times .

 

How gasoline is refined and what additives are added (or not) and their quantities also determines the price.
What is put in and how much is proprietary, so you'll never know unless you get it tested yourself.
That bargain basement fuel has a bargain basement price for a reason and none of them are good reasons.
Yes, it's that simple.

 

Amen to that. I try to go to good gas stations whenever I can myself.

 

You know what you and also missed..... is never seeing anyone with a Performance street car, vehicle or Motocycle(real biker not a wnna-be) buying gas at 7 eleven, Costco or other fuel stations way down the list of better fuels to use (unless they were posers) I wonder why. Auh maybe they knew something we didn't about the quality of fuels. NOT!

And those that said they never had problem using them well I am sure they thought that but then in every case they ate more engine parts got lower then the average MPG and never made as much power as they could have by using a better fuel. Now some will argue that but then I guess we can never prove otherwise except we know and they cant either .

I guess that why the Italian Tune-up" Truley came about, those using less expensive (cheap gas) poor fuels and needing to clear out the combustion chambers to run better. LOL
30 - 50 plus years ago auto service shops predominantly used a vacuum gauge to assist in tuning engines and the use of a vacuum gauge the mechanic could clearly see when the carburetor could not be dialed in the best because of poor quality fuels used.. Now adays many would look at the current and best MPG digital dash gauge which really is exactly what a vacuum gauge did and can see the same thing in real time the effects of a good quality fuel and the use of higher octanes as well.

 

pp-3-54 cx5 2023 Owners Manual -" TOWING " use min 91 octane when towing - hmmm devils in the details i suppose - pp 3-26 min octane 87 any lower can cause serious engine damage/ emissions system damage ...uh-yeah -

 

I think the better point is anyone that is a new owner of a vehicle any year and miles should take the time to read the owner's manual.

While I do enjoy helping members on various forums it is well obvious to me when someone never read the owner's manual.


One point both you and I have forgotten to mention, and it is a split hair of information but how the gas of choice, that supplier what they used to get their octane values. Also if they are augmented by a states mandate or regulation on what additional ingredients or the % of certain ingredients must be added to the fuel.

The more % of alcohol in the fuel the less total power will produced at any given stated octane value on the pump. The ECU can compensate for some changes but not as much as posted on the internet.

I have looked at the ECU tables(PIDS) on a factory program and there is not much fudge factor without going in and doing some manual changes to the files.
This is a short DATA logging from one of my customers I do ECU/EFI Calibration for on another platform. Each section must be accounted for when any singular change is made because one PID change effects all the other.

 

We have a couple skyactive's and over the years, 2013 for our 2.0, I have found that the extra cost of 91 over 87 is not that great when you factor in the improved increase in mileage. Toss in an occasional can of Gumout 30002 Multi and your car and wallet will be happy.