Vacuum Brake Booster: Service and Repair
REMOVAL
1. Remove the remote ground cable from the ground stud located on the left strut tower.
2. Correctly isolate remote ground cable when servicing vehicle by installing the ground cable insulator on the strut tower ground stud as shown . This will prevent accidental grounding of the remote ground cable.
3. If equipped, remove the vehicle's wiring harness connector from the speed control servo. Remove the 2 speed control servo mounting bracket to strut tower attaching nuts. Without removing speed control cable from servo, move speed control servo out of the way.
4. Remove the vacuum harness connector and electrical connector from the purge solenoid. Remove purge solenoid from vehicle.
5. Remove the vacuum hoses from the check valve located on the power brake vacuum booster.
6. Remove EGR valve transducer assembly and vacuum hoses from the EGR valve. Valve removal is necessary for required clearance to remove power brake vacuum booster from vehicle and not damage transducer during removal.
7. Remove the vehicle's wiring harness connector from the master cylinder brake fluid level sensor.
8. Remove the 2 nuts attaching the master cylinder assembly to the power brake vacuum booster.
9. Without removing the brake tubes from master cylinder, remove it from the power brake vacuum booster. Then carefully lower master cylinder and brake tubes as an assembly until it is positioned on top of the transaxle.
10. Locate the power brake vacuum booster input rod to brake pedal attachment under instrument panel. Position a small screwdriver between the center tang on the power brake booster input rod to brake pedal pin retaining clip. Rotate screwdriver enough to allow retaining clip center tang to pass over end of brake pedal pin. Then pull retaining clip off brake pedal pin. Discard retaining clip. Replace only with a new retaining clip when assembled.
11. Remove the 4 nuts attaching power brake vacuum booster to dash panel. Nuts are accessible from under dash panel in area of the steering column and pedal bracket assembly.
12. Slide power brake vacuum booster forward until mounting studs clear dash panel and then tilt up and rotate toward center of vehicle to remove.
CAUTION: Do not attempt to disassemble the power brake vacuum booster it is to be serviced ONLY as a complete assembly.
INSTALLATION
1. Position power brake booster onto dash panel.
2. Install and torque the 4 power brake vacuum booster mounting nuts to 29 Nm (250 inch lbs.) torque.
3. Using lubriplate, or an equivalent, coat the surfaces of the brake pedal pin that contact the power brake vacuum booster input rod.
4. Connect power brake vacuum booster input rod to brake pedal pin and install a NEW retaining clip.
Use only a new retainer clip DO NOT USE the old clip.
5. Position master cylinder on studs of power brake unit, aligning push rod on power brake vacuum booster with master cylinder push rod.
6. Install the 2 master cylinder to power brake unit mounting nuts. Tighten the 2 mounting nuts to a torque of 28 Nm (250 inch lbs.).
7. Install the vehicle's wiring harness connector on the master cylinder brake fluid level sensor.
8. Install the purge control solenoid on the left front frame rail. Tighten the purge control solenoid mounting bolt.
9. Install the EGR transducer assembly on the EGR valve. Install the vehicle wiring harness connector on the EGR transducer, ensuring the retaining clip is fully engaged with transducer.
10. Connect all previously removed vacuum hoses onto the power brake vacuum booster check valve.
11. If equipped, install speed control servo on the mounting studs in the left strut tower. Install the 2 speed control servo bracket mounting nuts. Tighten the 2 mounting nuts to a torque of 6 Nm (55 inch lbs.).
12. Check brake light switch for correct adjustment. If required, adjust stop lamp switch as necessary. See required procedure found at Lighting and Horns, Brake Light Switch, Adjustment.
13. Road test vehicle to ensure proper operation of the vehicles brake system.