Boost Gauge

The IPC displays the difference between the engine intake pressure and the atmospheric pressure as determined by the PCM. The PCM monitors the Manifold Absolute Pressure (MAP) sensor and sends a class 2 message to the IPC indicating the pressure. The boost gauge defaults to 0 psi (0 kPa) if:
^ The PCM detects a malfunction in the MAP sensor circuit.
^ The IPC detects a loss of class 2 communications with the PCM.