Air Bypass Valve: Description and Operation
ENGINE CONTROL COMPONENTSTurbocharger Bypass Valve (TCBY)
The TCBY valve(s) prevent backflow through the turbochargers when the throttle is rapidly closed to avoid undesirable noise. The high pressure downstream of the turbocharger is vented back to the intake air stream when the valve is open reducing pressure in the system.
Typical Turbocharger Bypass Valve:
