To remove the brake booster, it is necessary to have the air conditioning circuit evacuated by a refrigerant engineer. Depress the brake pedal several times so as to eliminate any vacuum in the brake booster, and remove the
Brake Master Cylinder and the windscreen wiper motor. Release the wiring harnesses from their clips, undo the two scrivets and take off the protective cover over the brake booster. Next, undo the fasteners and remove the air conditioning low-pressure pipe, plug or seal the openings to avoid contamination, and remove the O-ring seals, as new ones must be fitted. Unclip the high-pressure air conditioning pipe and get it out of the way, and prise the pressure sensor out of the booster if fitted. Disconnect the wiring plug, carefully spread the circlip and pull the pedal sensor off the booster, removing the O-ring seal for a new one when reassembling. Undo the unions and remove the two fluid pipes between the master cylinder and the ABS unit, again plugging or sealing the openings. Remove the lower facia panel on the driver's side and remove the two bolts to remove the upper timing belt cover. Raise the front of the car and place it securely on axle stands, then remove the seven Torx screws to remove the engine undershield if it is fitted. Support the engine using a trolley jack, using a block of wood between the head of the jack and the sump to avoid damage. Undo the bolts to remove the right-hand engine mounting assembly and drop the engine about 6 cm down. Remove the pin holding the booster pushrod to the brake pedal remembering that the pin cannot be completely separated from the booster pushrod and a new pin needs to be fitted when the engine is reassembled. Finally, undo the four nuts that hold the booster to the pedal bracket or bulkhead and manoeuvre the booster from the engine compartment. For refitting, reverse the removal process, ensuring that all of the nuts and bolts are done up to the specified torque, fit the master cylinder and windscreen wiper, check and bleed the hydraulic system if required and have the air conditioning system recharged by a suitably equipped specialist.