NOTICE: Do not run the engine without fluid. . .This can cause damage to the engine.

If the hydraulic brake booster system fails due to a loss of fluid, perform the following steps before starting the vehicle:

Clean and flush the hydraulic booster system when the power steering pump is replaced. Metal shavings from a worn power steering pump often contaminate the system. Disassemble and clean the booster head, and replace all of its seals and O-rings. Remove the pipes and hoses and blow them clean of all metal shavings. Refer to "Flushing the Hydraulic Booster System" and "Booster Assembly."

1. INPUT ROD SEAL: A damaged seal will show as a fluid leak from the vent hole in the mounting bracket. Remove and disassemble the booster. Check the bore of the input rod for any scratches that may cause the leak. If scratches are present, replace the housing cover. If no excessive scratches are present, replace all seals by using the booster seal kit.
2. POWER PISTON SEAL: A fluid leak at the brake booster vent of the common master cylinder, and a possible reduction in power assist, indicates damage to the power piston seal. If this occurs, remove and disassemble the booster. Check the piston for any scratches that may be the cause of the leak. If no scratches are present, replace all seals by using the booster seal kit.
3. HOUSING SEAL: If the housing seal is damaged, fluid will leak between the two housings. If this occurs, remove and disassemble the booster. Use the booster seal kit to replace the housing, input rod, and power piston seals.
4. SPOOL VALVE PLUG SEAL: If this seal is damaged, fluid will leak past the plug. Replace the seal, which can be done with the booster on the vehicle.
5. ACCUMULATOR SEAL: If this seal is damaged, fluid will leak past the accumulator cap. Replace the seal, which can be done with the booster on the vehicle.
6. RETURN PORT FITTING: Tighten the fitting to 10 N·m (88 lb in). If the leak continues, replace the seal ring under the fitting.