Subaru CAN Flex Fuel Upgrade + Fuel Pressure Kit WRX 2018-2021

Part Details:

The Subaru CAN Flex Fuel Upgrade & Fuel Pressure Kit is designed to give tuners accurate, real-time data needed to safely run ethanol-based fuels on Subaru WRX models from 2018–2021. This system provides direct ECU input for ethanol content, fuel temperature, and fuel pressure, allowing adaptive calibrations across multiple fuel blends.

Using modern CAN-based communication, this kit delivers reliable signal transmission with a clean installation that minimizes wiring complexity. It is ideal for vehicles running E85, blended ethanol fuels, or upgraded fuel systems where precise fueling data is critical for performance and engine safety.

CAN-Based Flex Fuel & Pressure Monitoring

This system continuously monitors ethanol percentage and fuel temperature while also providing real-time fuel pressure data. By supplying accurate inputs directly to the ECU, the kit allows tuners to create dynamic maps that automatically adjust to changing fuel blends such as 91 octane, E30, or E85.

Fuel pressure monitoring adds an additional layer of protection by helping identify fuel delivery issues before they become engine-damaging problems, making this kit a valuable upgrade for higher horsepower and ethanol-based builds.

Applications & Compatibility

This kit is specifically designed for Subaru WRX models equipped with the FA20DIT engine from 2018–2021. It is commonly paired with upgraded injectors, fuel pumps, and fuel system components to support increased power levels and advanced tuning strategies.

Key Features

• Complete flex fuel solution with ethanol content sensor and CAN expansion module
• Fuel pressure kit included for real-time fuel pressure monitoring
• Supports adaptive tuning across pump gas, blended ethanol, and E85
• CAN-based integration for reliable data transmission and clean installation
• Precision monitoring of ethanol content, fuel temperature, and fuel pressure
• Designed for Subaru WRX 2018–2021 with the FA20DIT engine

What’s Included

• Ethanol content sensor
• CAN expansion module
• Fuel pressure sensor and related components
• Required wiring and installation hardware

Frequently Asked Questions

Is tuning required after installation?
Yes. Professional ECU tuning is required to properly configure flex fuel and fuel pressure inputs and ensure safe operation.

Can this kit be used with upgraded injectors?
Yes. This system is commonly paired with upgraded injectors and fuel system components to support higher horsepower and ethanol-based builds.

Does this kit automatically adjust for different ethanol blends?
When properly tuned, the system allows the ECU to adapt dynamically to changing ethanol content for consistent performance and safety.

Recommended Supporting Fuel Components

• Fuel Injectors – higher ethanol content often requires increased fuel flow to maintain proper air-fuel ratios.
• Fuel Pumps – support the additional fuel volume needed for ethanol and higher power levels.
• Fuel Pressure Regulators – help maintain consistent fuel pressure across varying ethanol blends.
• Fuel Delivery Components – explore supporting fuel system parts designed to work together.

Learn more about COBB Tuning performance solutions and supporting components