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3-Port Boost Control Solenoid

Cobb's 3-port electronic boost control solenoid enables precise boost control and easy tunability in a tidy package that is a direct replacement for the factory solenoid. Eliminates boost fluctuations inerent in the OEM boost control system providing stable and repeatable boost control. Will easily control high boost levels. Uses low profile barbed hose fittings for compact installation and fittings are nickel coated for corrosion resistance. The solenoid is constructed using high quality materials and designed for longevity and moisture resistance. Comes with bracket, hardware, hose, and zip ties. Fits directly in place of original solenoid and plugs into factory harness.

Usually ships in 1 to 2 days.

Manufacturer: Cobb


  • Subaru WRX MY15+

What is the boost control solenoid and how does it work? The boost control solenoid is connected to the pressure signal for the turbo's wastegate. The ECU applies a duty cycle to the solenoid based on tables programmed in the engine mapping in order to control the opening of the wastegate. Based on the way the solenoid is installed, it either interrupts the pressure signal applied to the wastegate actuator or bleeds off part of the signal. The use of the boost control solenoid allows the wastegate to be held shut at boost pressures above that of the wastegate spring pressure.

What is the advantage of the Cobb solenoid over the factory one? The Cobb solenoid is capable of higher flow and faster reponse than the factory one. It can more accurately control the desired boost curve especially at elevated boost pressures.

Will the ECU need re-tuning after installation of this solenoid? Mostly likely re-tuning will be required to achieve correct boost pressures.