COBB Tuning Fuel Pressure Regulator to Fuel Rail Kit - 2008-2021 Subaru STI

Real-Time Fuel Pressure Data Through the Accessport

The Cobb CAN Fuel Pressure Kit for the 2008-2021 Subaru WRX STI adds real-time fuel pressure monitoring to the Accessport V3 without tapping into the vehicle's OBDII system. The sensor reads fuel pressure directly from the fuel rail and transmits it to the Accessport via a dedicated CAN bus connection. For builds running elevated boost and modified fueling, knowing fuel pressure in real time is essential — a fuel pressure drop under boost is the warning before a lean condition develops.

Protect the Engine — Know Your Fuel Pressure

The OEM fueling system on the GR/VA STI is adequate for stock power levels, but as boost and power increase, fuel system limitations show up in data before they show up as engine damage. The Cobb CAN Fuel Pressure Kit gives the Accessport V3 the sensor data it needs to display and log actual fuel pressure. A tuner can see exactly what the fuel system is doing under load — and catch a problem before it becomes expensive.

Plug-In CAN Connection — No ECU Wiring Required

The Cobb CAN Fuel Pressure kit connects to the vehicle's existing CAN bus through a simple plug-in harness — no splicing into the ECU, no custom wiring. The Accessport V3 is required to use this kit, as it's the device that reads the CAN data and displays or acts on it. Installation is straightforward and reversible.

Key Features

• Platform: 2008-2021 Subaru WRX STI
• Plug-in CAN bus connection — no ECU wiring or splicing required
• Requires Cobb Accessport V3 for sensor data display and tune adjustment
• Real-time fuel pressure monitoring — displayed and logged on Accessport V3
• Fully reversible installation

Fitment Notes

• Platform: 2008-2021 Subaru WRX STI
• Requires Cobb Accessport V3 — does not work without Accessport
• Confirm MT vs CVT compatibility by SKU before ordering

Straight From Subispeed

The Cobb CAN system is the right approach to fuel monitoring on the GR/VA STI — plug-in installation, Accessport integration, and automatic tune adjustment without a separate fuel management system or wiring harness. For any build running elevated boost, fuel pressure monitoring is the kind of data that pays for itself the first time it catches a problem before the engine does.

What's Included

• Cobb CAN Fuel Pressure Kit — 2008-2021 Subaru WRX STI
• CAN bus harness and sensor
• All mounting hardware

About Cobb Tuning

Cobb Tuning has been developing performance parts and tuning solutions for Subaru vehicles since 1999. Based in Austin, Texas, Cobb built their reputation on the Accessport — the most widely used Subaru ECU tuning device on the market — and expanded that into a full ecosystem of intake, exhaust, drivetrain, and engine bay accessories engineered specifically for the platforms they support. Every Cobb product is developed in-house and validated on their own test vehicles before it reaches customers. Subispeed carries the full Cobb catalog because their engineering standards and platform-specific development process consistently produce parts that work exactly as advertised.