Mitsubishi 1993 3000GT, Technical Information Manual

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valve. As a result, turbo pressure corresponding to
driving conditions can be obtained.
The engine control unit turns the power transistor in the unit on and,
when normal current (duty 100%) flows in the waste gate solenoid
valve coil, the waste gate solenoid valve does not open if turbo
pressure does not rise above the set pressure of the waste gate
actuator spring since some of the turbo pressure used in the waste
gate actuator leaks out.
On the other hand, when current does not flow in the waste gate
solenoid valve coil (duty 0%), the waste gate valve opens if turbo
pressure rises to the set pressure of the waste gate actuator spring
since no pressure leaks out.
Consequently, by using duty control for the waste gate solenoid
valve, turbo pressure can be controlled in a range from 00/0 to
100% duty.
This duty control is performed in cycles of approximately 60 ms.
FUEL - Control System
TURBO PRESSURE CONTROL
Turbo pressure used in the waste gate actuator is
controlled by duty control of the waste gate solenoid