Mazda Mazda CX-9 2016-present Fuel System Specifications

The 2016-Present Mazda CX-9 is designed to run on regular unleaded gasoline with an octane rating of 87 or higher. Using premium fuel (91 octane or higher) is optional and may enhance performance slightly, but it is not required. Mazda recommends avoiding fuels with more than 15% ethanol (E15) as they can damage the engine and fuel system components.

Mazda recommends inspecting the fuel system during every oil change (approximately every 7,500 miles or 12 months). Replace the fuel filter every 60,000 miles or as specified in the owner's manual. Regularly check for fuel leaks, ensure the fuel cap is tight, and use fuel system cleaners periodically to maintain optimal performance and fuel efficiency.

To replace the fuel filter on a Mazda CX-9, first, locate the fuel filter, typically near the fuel tank. Relieve fuel system pressure by disconnecting the fuel pump fuse and running the engine until it stalls. Disconnect the battery, remove the old filter, and install the new one, ensuring proper orientation. Reconnect all components, start the engine, and check for leaks.

If your Mazda CX-9 has poor fuel efficiency, check for clogged air filters, improper tire pressure, or a malfunctioning oxygen sensor. Ensure you are using the recommended fuel type and avoid excessive idling or aggressive driving. If issues persist, have a professional inspect the fuel injectors, spark plugs, and engine control module for faults.

To optimize fuel performance, maintain regular servicing, including oil changes and air filter replacements. Use high-quality fuel and avoid overloading the vehicle. Drive smoothly, avoid rapid acceleration, and use cruise control on highways. Keeping tires properly inflated and reducing unnecessary weight can also improve fuel efficiency.