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Turbo pressure control

Turbo pressure control


The turbo pressure in the intake manifold depends mainly on engine speed and load. At higher loads, however, turbo pressure is restricted by the wastegate.

The wastegate is a flap valve which closes or opens the "bypass" channel beside the turbine. The flap valve is affected by a rod from a diaphragm box positioned by the compressor housing. The diaphragm is acted on by the vacuum and a spring in diaphragm box has the function of closing the flap.

During low and normal load, the wastegate valve for turbo pressure is closed. When the load increases and the turbo pressure is approaching maximum, the "bypass" channel opens and the pressure is reduced.

The pressure is monitored continuously by a pressure sensor fitted on the induction manifold.