Within their HB Automatic Maintenance Program, Honda and all 2006 and before Acura vehicles need multiple brake check routines. Squeeze the brake pedal several times when the engine is turned off. If there's no difference in the reserve space left before the pedal returns to the floor, start the engine and do it again. Regular functioning means the pedal gets lower each time. To check for airtightness in the booster, cycle through these tasks: start the engine, let it run for a minute or two, then stop it. Press down slowly on the brake pedal three times in a row - if the pedal drops when you first press, then comes back up after pressing two more times, your booster is tight. When the engine is running, keep your foot on the brake pedal and turn off the engine; the booster passes this test if your brake pedal reserve distance stays the same for 30 seconds while not changing. Because removing the power unit needs complex tools most homeowners don't have, it's safer to let professionals install new or rebuilt power units if you run into problems. Take off the master cylinder, cut connections for cruise control and the accelerator when needed, and disconnect the large hose from the power brake booster. When inside the passenger area, remove the pin that holds the joint and disconnect the pushrod connector from the brake pedal connection. Disconnect the nuts holding the booster in place by the firewall. Lift the booster unit slowly and steady from its spot on the engine compartment, taking care to not flex the brake hydraulic pipe. First, put the booster unit in place and fasten the holding nuts. Next, join the pushrod to the brake pedal and use a new lock pin for the pushrod's joint pin, as suggested. Last, put the master cylinder back in place, attach the vacuum tube, clean any air from the brakes, and verify brake performance before getting back to regular car driving.