2009 Chevrolet Cobalt Owner's Manual - Page 162

Boost Gage This gage is automatically centered at zero every time the engine is started. Actual vacuum or boost is displayed from this zero point. Changes in ambient pressure, such as driving in mountains and changing weather, will slightly change the zero reading. Reconfigurable Performance Display (RPD) For vehicles with the RPD, the screen displays information that can be used to monitor vehicle performance. The RPD knob located next to the screen is used to configure the display and select information to be viewed. A short video plays whenever the ignition key is turned on. Press the RPD knob to stop the video and go directly to RPD displays. United States Canada If equipped, this gage is located near the driver side of the instrument panel cluster. This gage indicates vacuum during light to moderate throttle and boost under heavier throttle. This gage displays the air pressure level in the intake manifold before it enters the engine's combustion chamber. 3-38