Cobb 18-21 Subaru WRX CAN Flex Fuel Upgrade (Module/Harness/Bracket/Ethanol Sensor)-COBB-COBB344650
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Cobb 18-21 Subaru WRX CAN Flex Fuel Upgrade (Module/Harness/Bracket/Ethanol Sensor)

COBB
COBB344650
731946518921
Flex Fuel Kit
20+ Units In Stock - Ships Next Business Day
$ 1,035.00
$ 1,035.00

SKU: B344650   |   UPC: 731946518921

COBB CAN Flex Fuel Upgrade Kit – 2018-2021 Subaru WRX (FA20DIT)

The COBB 344650 Flex Fuel kit transforms 2018-2021 Subaru WRX performance by enabling full E85 use with real-time ethanol content and fuel temperature monitoring via CAN bus directly to the Accessport V3. This plug-and-play solution includes the Continental ethanol sensor, harness, firewall bracket, and fittings for the cleanest inline installation on feed or return lines. Unlock automatic blending, cold-start compensation, and precise mapping for reliable power across any fuel mix.

Key Features

  • True CAN Bus Integration: 100% digital connection with zero latency for instant Accessport data.
  • Continental Ethanol Sensor: OEM-grade sensor measures 0-100% ethanol plus fuel temperature with proven durability.
  • Live Ethanol % & Fuel Temp: Real-time display on Accessport V3 for monitoring and tuning confidence.
  • Full E85 Support: Auto-blend maps and cold-start compensation handle any gasoline-E85 ratio.
  • Made in the USA: CNC aluminum bracket and lifetime warranty ensure long-term reliability.

Product Notes

  • Fits 2018–2021 Subaru WRX FA20DIT only; requires Accessport V3 with latest firmware.
  • Will NOT fit 2015–2017 WRX (use 343650) or STI models.
  • In stock – ships same or next business day in official COBB retail box.

Installation Notes

  • Professional installation recommended.
  • 60–90 minute DIY install mounts inline on fuel feed or return line with -6 AN fittings.
  • 100% plug-and-play harness; no cutting factory wiring; Accessport auto-detects kit post-install.

This Part Fits

Year Make Model Submodel
2018-2021 Subaru WRX FA20DIT

Why Choose COBB Tuning?

  • #1 name in Subaru performance for over 20 years.
  • Engineered and manufactured in the USA.
  • Proven on every 500–800+ hp FA20 build worldwide.

Frequently Asked Questions

  • Q: Will this work on my 2017 WRX?
    A: No, 2015–2017 WRX requires COBB 343650 kit.
  • Q: Do I need a custom tune?
    A: No, COBB provides free OTS Flex Fuel maps for immediate use.
  • Q: Can I run E85 immediately?
    A: Yes, flash the Flex Fuel map via Accessport after install for full capability.

Shipping & Handling

  • Method: UPS/FedEx Ground
  • Availability: In stock - ships same or next business day
  • Packaging: Official COBB retail box, 11.5 x 9 x 3 inches
  • Weight: 1.8 lbs

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