Turbocharger Vane Position Control Solenoid Valve
WARNING: This page is about a different car, the 2009 GMC Sierra, 2009 GMC Cab & Chassis Sierra, 2009 Chevrolet Silverado, and 2009 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
The vane position control solenoid valve (2) works in conjunction with oil pressure to control the turbocharger vanes. The ECM uses a pulse width modulation on both control circuits to control the solenoid valve. The solenoid valve allows the engine oil pressure to move a piston. This piston rotates the unison ring, thus controlling the engine boost dependent upon engine load.