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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