Wastegate: Description and Operation

PURPOSE
The wastegate valve is connected to the wastegate actuator pot by means of a metal rod.

LOCATION
The valve is located inside the turbine outlet housing and is not serviceable alone.

OPERATION
When boost pressure approaches 7.4 psi in the intake pipe, the wastegate actuator diaphragm pushes the rod out, opening the wastegate valve. A passage around the turbine rotor allows exhaust gas and pressure to bypass the turbine, thus slowing rotor and impeller speed. When boost pressure drops below 7.4 psi in the intake pipe, the actuator retracts the rod, allowing the wastegate valve to close. Full exhaust pressure is now directed to the turbine rotor.