Very informative answer! Thank you so much for your insight, the video and taking your time to write this. I will double-check my manual but it's not a turbo-charged vehicle, as you alluded to at one point. This makes me feel better. I'll just use a fuel system cleaner, perhaps with every oil change or so., as you suggested. I've heard and used a number of them before--are any you suggest or any bad ones? Thanks again!!!Pretty sure its regular even in your model year but things may have changed?? Ive been using regular unleaded "cheap" gas for last 5 years with the occasional fuel system cleaner bottle thrown in which I do for all cars regardless. The topic of regular vs higher octane is another one of those controversial broscience things in the car world where people will swear by anecdotal experiences and word of mouth/ things they mightve seen online in other forums which swear by other things lol.
Short version: yea just use regular
Long version: Basically for 'modern' cars, everything is controlled electronically. Unless you tune the ecu specifically for the combustion capabilities of higher octane fuel, you will almost never see a difference compared to cheap gas if your car says to use regular by manufacturer. The mpg difference is heavily biased because even just stepping a little bit harder on the accelerator, you are making the car burn more fuel. Someone might put premium fuel and drive more economical because of the cost impact and all of a sudden they might see 'more mpg'. The other difference is resistance to knock and how clean the fuel burns. However the car is already tuned by the manufacturer to run perfectly fine with regular gas. If you had a infiniti or bmw etc which requires premium higher octane gas, you might notice a loss of power if the car is advanced enough to detect the fuel isnt combusting as expected to prevent engine knock, or it might just misfire and set off check engine lights and hopefully just minimal damage occurs. The majority of the time this happens is when people put in, incorrect fuel in a car that requires higher octane due to high compression ratios.The exception is turbocharged vehicles since modern ones almost always need premium fuel to prevent misfires and run efficiently. Thankfully for the cx-3 we are basically a slightly taller econo-box car which works in our favor. Theres also a ton of videos online explaining the pros and cons of such things but they usually go into the scientific theoretical manner of it and not actual practicality. The other thing people will swear by is how clean the fuel is. Im not even going to touch this topic except for watch this or just skip to 9:35 and see for yourself an example of the carbon buildup using one of the more expensive fuel(because of supposed added detergents) around here compared a cheap gas.
Gas might be cheaper now but there still isnt much of a benefit to using the higher octane gas for the cx-3 that would justify an additional dollar(ish) per gallon. If anything tossing in a fuel system cleaner bottle in the fuel tank every oil change or so, heck even once a year if anything, will probably clean more deposits than by using premium fuel.
Some people like the peace of mind of thinking theyre doing something they believe is helping so that works for them. Personally my rule of thumb is to try to have some logic behind my actions and understand how things work to try to mitigate any future issues.
Anything thats a 'complete' cleaner and not just those small tiny lucas fuel injector cleaners. This one is a little harder to answer but the only thing I can find is things with the additive PEA are the ones which actually do something based on when I looked into it a while back. Techron or gumout or anything really with PEA are the ones I usually get. Major chain autostores usually have a rotating sale on fuel system cleaners. I would just also say to not believe all the advertising material on the bottles also. In theory engine with massive carbon deposits would be less efficient than a clean one and using anything which cleans said deposit would theoretically improve mpg, but in reality you wouldnt know how much its actually doing if anything especially when you cant see how much carbon buildup exists if any. Its sort of like how tv commercials say 'x MAY HELP with y' but its under a specific set of circumstances in a testing environment. If anything it doesnt hurt to stay on top of it for peace of mind in my opinion lolVery informative answer! Thank you so much for your insight, the video and taking your time to write this. I will double-check my manual but it's not a turbo-charged vehicle, as you alluded to at one point. This makes me feel better. I'll just use a fuel system cleaner, perhaps with every oil change or so., as you suggested. I've heard and used a number of them before--are any you suggest or any bad ones? Thanks again!!!