Booster Functional Test
WARNING: This page does not describe the selected car, but rather 26 other vehicles, including the 1992 GMC Yukon, 1992 GMC Vandura Special, 1992 GMC Vandura, 1992 GMC Value Van, and 1992 GMC Suburban. However, it is still accessible from the selected car via links, so may be relevant.
With engine off, press brake pedal several times to deplete accumulator reserve. Press and hold brake pedal with about 40 lbs. (18 kg) pressure. Start engine. Brake pedal should fall slightly, then push back against foot. If no action is felt, booster is not operating properly.