Turbocharger WASTEGATE Control (OVERBOOST)

The turbo pressure is controlled by the ECM. When the turbo pressure is not controlled by ECM, the pressure acting on the wastegate control diaphragm is equal to the turbo pressure.

When the turbo pressure is controlled by the ECM, pressure on the wastegate control diaphragm is released to the atmosphere through the Vacuum Switch Valve (VSV).

Trouble code 31 is registered when turbo pressure has risen to an abnormally high level. Code 31 appears under the following conditions:

• No MAP sensor signal. Neither code 33 nor 34 is registered.
• MAP has dropped below specified value within 0.2 seconds after the High Load Fuel-Cut Mode was reached.