Boost Gauge - Supercharger: Description and Operation
BOOST GAGE
The boost gage is a measure of the engine manifold air pressure. The powertrain control module (PCM) sends a PWM signal to the boost gage indicating the manifold air pressure. The boost gage displays the engine air intake above and below the ambient pressure. The PCM controls the engine boost pressure with the boost control solenoid. The engine boost system pumps more air than the engine would normally use into the intake manifold. The excess air pumped into the intake manifold, creates the engine boost effect. The maximum boost pressure is about 83 kPa (12 psi).
The boost gage performs a self test by the gage dial moving to 0 kPa (0 psi) when the ignition is turned ON and the boost gage is also turned ON. Refer to Supercharger Description and Operation or Boost Control System Description for the 2.0L engine.