ECU Power Module

The iBuildRacecars Flex Fuel Sensor Kit provides a solution for data logging and monitoring the ethanol content of fuel in compatible Subaru vehicles. This kit features a proprietary controller that generates its own onboard 12V supply, which simplifies installation by reducing wiring needs and improving overall reliability. The system is engineered to properly reference the ECU's 5V power, ensuring the most consistent and accurate data output. The kit includes a Continental Flex Fuel Sensor, a mounting bracket, the Flex Fuel Sensor Controller, and a custom wiring harness. Hose assemblies are provided for both 2008+ STI and WRX models. The wiring harness is detachable from the controller, simplifying troubleshooting and repairs. Key benefits include automotive-grade wiring, no need for a 12V supply from the rear O2 sensor, and top-side installation that avoids the need to crawl under the vehicle. The controller features a potted housing with a solid pin connector for enhanced durability. Compatibility is specified for 2008-2021 Subaru WRX and 2007-2021 Subaru STI models. The vehicle must be tuned specifically for flex fuel to utilize this kit; it is not compatible with Cobb “Green Speed” tunes. Users should consult their tuner regarding tuning options, as compatibility can vary. If replacing another brand of flex fuel controller, a retune may not be necessary due to similar voltage outputs. Note that due to limited TGV plugs, only two of the following can be run simultaneously: Secondary Injection Controller, Flex Fuel Sensor Kit, and Fuel Pressure Sensor Kit. Custom wiring may allow for all three.