u/EzGo48

• "⁠Engine Damage: E15 can cause long-term damage such as clogged injectors, worn seals, and premature engine repair. "Your (and my) Skyactiv engine is rated for a max of 10% ethanol, aka E10. Using 15%, aka E15 aka 88 octane might seem cheaper and make you feel better with the higher octane number, but it can damage your engine over time: clogged injectors, worn seals and injectors."

• ⁠"Warranty Issues: Using E15 may void your warranty coverage for engine damage. "Vehicle damage and drivability problems resulting from the use of the following may not be covered by the warranty. Gasohol containing more than 10 % ethanol."

I have a 2023 CX-5 Signature and seeing as all the gas companies in Ontario Canada are in the process of transitioning to a E15 blend, I can now expect long term damage to the fuel system it seems. Also, how is this going to affect trade-ins in the future when no other auto manufacturers will want to deal with Mazda cars. Amazing that Mazda knowing full well of the transitioning to E15 fuel in that the new 2026 CX-5 is still E10 only compatible.

I own a 2023 Mazda CX-5 Turbo and the 2 stations near me (ESSO, SHELL) in Ottawa(Kanata) have no display stickers on their pumps as to the % of ethanol content being used. I thought it was a law in Ontario to display the Ethanol content but apparently it’s not. By the way since 2025 the Ethanol content in Ontario can now be up to 11% although 10% is still the norm, but it is now being slowly accelerated to 15%. According to Mazda “This vehicle can only use fuels containing no more than 10% ethanol by volume. Damage to the vehicle may occur when ethanol exceeds this recommendation”.

Mazda vehicles are not alone with this problem.

“While the EPA has approved E15 (15% ethanol) for vehicles from model year 2001 and newer, several manufacturers have historically advised against its use or have not formally approved it for all their models, particularly in older non-flex-fuel vehicles.

Using E15 in non-approved vehicles can potentially void warranties and cause damage to fuel systems. © WordPress VIP +4

Vehicles/Makes that generally do not accept or recommend E15 include:

• Mercedes-Benz, Mazda, and Volvo: These manufacturers generally do not specifically list E15 as an approved fuel, as of late 2023.

• BMW/Mini: Do not recommend E15, noting that their engines are designed for up to 10% ethanol (E10).

• Mitsubishi: Generally listed among those not certifying their vehicles for E15.

• Older Vehicles (Pre-2001): E15 is not approved for any car built before 2001.

• Small Engines/Recreational Vehicles: Motorcycles, boats, snowmobiles, and lawnmowers should not use E15.

• Specific Subarus: While some newer models are approved, some older or specific models (e.g., certain 2015/2022 2.5L models) are noted as not approved for blends higher than 10%.”

So now I look forward to more than likely fuel component issues down the road. And what Auto Manufacturer would want to take Mazda’s as trade-in’s.