Another discussion having no end. Ethanol is there to protect the enivironment. That’s what “they” say. However, using high octane gas without ethanol and with a normal (so no wannabe Max Verstappen habits) driving style you WILL get higher mileage because gas without ethanol has a higher caloric value. So no rocket science here. Using high octane gas adds up because the engine can do its job better, less fuel per mile/km. No rocket science either. On top of that over time ethanol WILL cause problems like described such as clogged fuel injectors and problems with the build up of water in the tank. A not optimal running engine will emit more unwanted fumes than one that runs flawlessly, no rocket science here either. The fuel treatments used by dealerships offer only a temporary and marginal solution, the intervals for servicing are simply too far apart depending ofcourse how often the car is used. Last time I had my car in for regular maintenance and the dealership asked me what type of gas I use. I told them eiter BP or Total tier gas, E5 98 (same as 93 in North America by the way). He told me in my case the injector treatment fluid was not needed. I never had any problems whatsoever so far. A clean engine, also the ones with double port fuel injection like A25A in the current RAV4 and other models, runs far cleaner, and as a consequence, has far less emissions than a so so running engine running on the “environmentally friendly” fuels “they” want us to believe these fuels are. If one insists on the use of E10 or E15 (E15 not available in Europe as far as I know) after what I said, make sure the tank is topped up as much as possible. Certainly if the car is hardly ever used. That partly solves the moisture problems that come with ethanol.
