BMW F Chassis Rear Mount CANbus Flex Fuel & Low Fuel Pressure Sensor Kit for N20, N55, & S55

Know your exact ethanol content in real-time with our new LED display or by using the BMS CANflex or JB4 mobile app on your smartphone or tablet.

This new rear mount ethanol sensor kit conveniently installs above the fuel pump, under the rear seat, providing ethanol mixture and low fuel pressure readings via CANbus to your ECU. It's compatible with both flash only tunes and JB4 tuning systems. Includes our new CANflex ethanol content analyzer (ECA) using the standard 0xEC CANbus ethanol format. Low fuel pressure is transmitted in the 3rd byte.

For those running a JB4, the new low fuel pressure signal provides an additional safety map trigger. If running port injection, low fuel pressure can also be incorporated into your port injection mapping ensuring consistent performance even in situations where low fuel pressure is dropping.

For flash only cars your tuner will finally be able to monitor your low fuel pressure to determine if there is sufficient pressure for your tuning needs. Compatible with JB4, MHD, BM3, and all tuning systems that use the standardized 0xEC CANbus ethanol format. We can also customize the CANbus commands if needed, just email us the details.

The kit features heavy-duty stainless braided fuel line, Burger Motorsports CNC machined fittings, and unlike other similar looking kits was designed to minimize restrictive bends and maximize fuel flow.

Download the free BMS CANflex app here:

Vehicle Fitment

BMW 1 Series
• 2012-2014 N55 BMW F20 F21 M135

BMW 2 Series
• 2016-2022 F87 N55 M2 and S55 M2 Competition
• 2014+ N55 BMW F22 F23 M235i

BMW 3 Series
• 2012-2013 N55 BMW F30 F31 335i/ix/Active Hybrid/xDrive
• 2015-2020 F80 S55 M3

BMW 4 Series
• 2014-2015 F32 F33 F36 435i / 435ix including Gran Coupe
• 2015-2020 F82 F83 S55 M4, M4 GTS

BMW X Series
• 2012-2014 N55 X1

Note: If your EKP doesn't have the CANbus wires going to it, you will need to find the twisted pair of wires in the wire bundle next to the EKP as show below. The twisted pair of wires will be a red wire and a blue wire with a red stripe. Once you make your connections and power on the car, open the enclosure to verify the green light is blinking and communicating. If the light is solid green, that means you have power but do not have communications and have a bad connection or the wrong set of wires.