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FLX01 - Flex Fuel Sensor Kit

  • Backed by real installs and tuning experience at FAST of West Chester


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Regular price $549.99
Sale price $549.99 Regular price $599.99 You Save $50.00!
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This kit is designed to provide a way to data log and monitor the ethanol content of fuel on most new Subaru Vehicles. Our proprietary controller reduces complications by generating its own on board 12V supply to power the sensor. This reduces wiring, installation time and improves reliability. Our system also properly references the ECU 5V power to provide the most consistent and accurate data. We have supplied hose assemblies for both the 2008+ STi and WRX in a single kit to reduce complication and confusion when ordering. The kit also comes with a custom wiring harness that can be detached from the controller to make any troubleshooting and repairs simple and painless.

Since the cars only have two TGV plugs capable of receiving inputs you cannot run our Secondary Injection Controller, Flex Fuel Sensor and Fuel Pressure Sensor kits all at the same time. You can only run a maximum of two of these three items. The SIC can be wired as power only in order to utilize all three but a custom harness must be made.

Compatibility:
2008 - 2021 STi
2008 - 2021 WRX

Tuning:
Works with most fuel management systems but the car must be tuned specifically to run flex fuel. This will not work with Cobb “Green Speed” tunes. We will be releasing a “Green Speed” compatible kit in June. Please work with your tuner to understand what options they have to tune your car as compatibility may vary tuner to tuner.

This kit has the same voltage output of other popular kits. Retuning your car most likely will not be required if you are just replacing another brand of flex fuel controller.

Key Benefits:

  • Replaceable wiring harness that will be sold separately

  • Automotive grade wiring

  • No need for 12v supply from rear O2 sensor (common failure point)

  • Installation can be done from the top with no need to crawl under the car

  • Properly referenced analog output from ECU 5V for better accuracy

  • Potted housing with solid pin connector for the ultimate in durability

Included in the kit:

Continental Flex Fuel Sensor
Flex Fuel Sensor Bracket
Flex Fuel Sensor Controller
Wiring Harness
Fuel Lines for both the 2008+ STi and WRX


  • Earn FAST points on this part!
  • Backed by real-world installs
  • FAST WC Team Approved

FLX01 - Flex Fuel Sensor Kit

$549.99

Why Drivers Choose FAST of West Chester

  • I can't recommend this place enough. Being able to trust a shop in the performance world is big. The 2hr drive to get there, is worth knowing the job will be done right. Very happy to have found this shop, to
    support my builds going forward.


    Donald Wojnar
  • I recently had the pleasure of working with FAST of West Chester for some performance upgrades on my 2022 WRX, and the experience was nothing short of exceptional. I opted for a Borla S-Type exhaust and Cygnus Coilovers, and the team at FAST nailed the installation, fitment, and setup to a T.


    Adam Cranston
  • The team at FAST are excellence in every way. First, I consulted with Dave on mods for my HPDE track car. He listened and advised me on the best parts & mods to achieve my goals. He was patient & gave me space to research the options presented & worked with me through several changes before we built. Second, the build execution was flawless, proper heat shielding, bracing and poly everywhere. All components worked as advertised.


    Bryce Budd
  • This place has been my go to shop for all things Subaru. From simple service to performance parts and tuning, they have been top notch.


    William Brunell
  • Excellent shop. They installed a Cobb Stage 2 DP and Whiteline Sway bars and end links on my 2013 WRX. The work was done right and clean. The estimate was accurate. They were very knowledgeable, friendly and gave me the straight scoop on exactly what I was getting for the money
    and what I needed to get where I want to be with it. I'd recommend them
    to any car enthusiast.


    Devin Greco
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Does it come with a warranty?

Most products we carry include a manufacturer warranty. Since we work with top performance brands, warranty coverage can vary by product. If you have questions about a specific item, reach out — we’re happy to help.

Do you offer installation help or advice?

Yes — we don’t just sell parts, we install and tune them too. FAST of West Chester is a real performance shop, and we’ve worked hands-on with many of the products we carry. If you have questions about fitment, installs, or building your setup, our team can point you in the right direction.

How fast is shipping?

Many of our products ship the same day or next business day, depending on availability. We work hard to get parts out fast so you can get your build moving without delays.

What’s your return policy?

Returns for exchange or refund are accepted within 30 days of receiving your order. Items must be in new, unused condition and in original packaging. If you have any questions, our team will help make the process easy.

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