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Mazda 3 Bluetooth Flex Fuel Kit for the 2021+ 2.5L Turbo

Mazda 3 Bluetooth Flex Fuel Kit for the 2021+ 2.5L Turbo

1 reviews

$479.95
Free Shipping In The USA
Free Bluetooth App Control
Free Firmware Updates
Reliable & Fully Reversible

Stop Guessing. Start Knowing Your Exact Ethanol Content.

Running E85 on your 2021+ Mazda 3 2.5L Turbo? Ethanol content at the E85 pump can vary from E50 to E85 or higher depending on season and station. Regular premium gas can have up to 10% ethanol at some stations. No more calculating gallons at the pump and guessing ethanol percentage. Just open the app and know.

Key Features

• Real-time ethanol content monitoring via Bluetooth
• Displays exact ethanol percentage (E-content) in the Fuel-It! or JB4 app
• 0–5V analog output for JB4 or flash tuning integration
• Genuine Continental ethanol sensor for OEM-grade accuracy
• Plug and play fuel line integration
• Ethanol safe PTFE fuel lines and fittings
• Installs in approximately 30 minutes
• No cutting or permanent modification required

Why You Need an Ethanol Sensor on Your Mazda 3

E85 pumps rarely dispense true E85. Seasonal blends can drop into the E50 range without notice. If you’re tuning for ethanol, this matters.

With this kit you can

• Dial in your exact E85 blend every fill-up
• Avoid running too much ethanol on a pump gas map
• Maximize timing and boost safely on ethanol maps
• Maintain consistent performance at the track
• Protect your engine from unknown fuel mixtures

The Bottom Line

If you’re running E85 on your turbocharged Mazda 3, a flex fuel sensor isn’t optional, it’s essential.

Power, consistency, and safety all start with knowing exactly what’s in your tank.

Download the Fuel-It! ECA app here:

Vehicle Fitment

• 2021+ Mazda 3 SKYACTIV® 2.5L Turbo

    * For the Mazda JB4 platform connect the white wire to position #4 on the JB4 25 pin harness. Select WMI Ethanol Setup option 0 to enable pin location 2/3/4 flex fuel input.



    Install Video


    Product Video