Circuit/System Description

WARNING: This page is about a different car, the 2010 Pontiac G5 and 2010 Chevrolet Cobalt. However, it is still accessible from the selected car via links, so may be relevant.

The boost gauge is a measure of the engine manifold air pressure. The powertrain control module (PCM) sends a PWM signal to the boost gauge via the boost gauge signal circuit. The boost gauge displays the engine air intake above and below the ambient manifold 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). When the ignition is turned ON and the boost gauge is ON, the boost gauge performs a power up self test as controlled by the PCM. The boost gauge dial moves up to 0 kPa (0 psi) to indicate the boost gauge passed the self test. Power is provided to the boost gauge via the ignition 1 voltage circuit.