SECTION T MAZDA MX-5 1994 Workshop Manual

N ENGINE SPEED SENSING POWER STEERING TROUBLESHOOTING GUIDE Steering feels heavy - - Poor lubrication, foreign material, or abnormal wear of steering ball joint Stuck or damaged lower arm ball joints lmproper steering pinion preload Damaged steering gear Malfunctioning steering shaft joint Problem I lmproperly adjusted wheel alignment Possible Cause 1 Malfunctioning steering gear lncorrect tire pressure Loose or damaged oil pump drive belt Low fluid level or air in fluid I Leakage of fluid I Insufficient oil pump pressure Steering wheel pulls lncorrect tire pressure to one side Unevenly worn tires ( Weak front spring General instability while driving Worn or damaged stabilizer and/or upper or lower arm bushing Dragging brake Loose lower arm lmproperly adjusted wheel alignment lncorrect tire pressure Damaged or unbalanced wheel Worn or damaged steering joint(s) lmproper steering pinion preload Weak front coil spring Worn or damaged stabilizer and/or upper or lower arm bushing Malfunctioning shock absorber Cracked or worn engine mount Cracked or worn transmission mount Shake (Steering wheel vibrates up/ down) Shimmy (Steering wheel vibrates left1 right) lmproperly adjusted wheel alignment Excessive tire and/or wheel runout Loose lug nuts Unbalanced wheel(s) Excessive steering wheel play Poor steering wheel return Cracked or worn steering gear mount Loose steering gear mounting bolts Stuck or damaged steering ball joint Excessive tire and/or wheel runout Loose lug nuts Unbalanced wheel@) lncorrect tire pressure Unevenly worn tires Malfunctioning shock absorber Loose shock absorber mounting bolts Stuck or damaged lower arm ball joint Cracked or worn suspension bushings Damaged or worn front wheel bearing lmproperly adjusted front wheel alignment Worn steering gear Worn or damaged steering joints Worn or damaged lower arm bushing Loose steering gear mounting bolts Worn linkage or tie-rod ball joint lncorrect tire pressure Stuck or damaged steering joints lmproperly adjusted front wheel alignment lmproper steering pinion preload Ball joint not operating smoothly Steering shaft contacting something Action Lubricate or replace Replace Adjust Replace Replace Adjust Replace Adjust Adjust or replace Add fluid or bleed air Repair or replace Replace Adjust Replace Replace Replace Repair Tighten or replace Adjust Adjust Adjust or replace Replace Adjust Replace Replace Replace Adjust Replace Tighten Adjust or replace Replace Replace Replace Tighten Replace Replace Tighten Adjust or replace Adjust Replace Replace Tighten Replace Replace Replace Adjust Replace Replace Replace Tighten Replace Adjust Replace Adjust Adjust Replace Repair Pagelsection N-25 section R N-32 N-25 N- 9 section R N-25 section Q N-37 N-21,22 - N-34 section Q section Q section R section R section P section R section R section Q section Q N- 9 N-32 section R section R section R section R section Q section Q section Q section B section J N-26 N-25 N-25 section Q section Q section Q section Q section Q section R section R section R section R section M section R N-25 N- 9 section R N-25 N-25 section Q N- 9 section R N-32 N-25 N- 9 Gartner Banana

ENGINE SPEED SENSING POWER STEERING N TROUBLESHOOTING GUIDE (CONT'D) Possible Cause I Problem Abnormal noise from steering system Loose oil pump Loose steering gear Loose oil pump bracket Drive belt loosettight Air in system Malfunctioning steering gear Malfunctioning oil pump Obstruction near steering column or pressure hose Loose steering linkage Worn steering joints Action Tighten Tighten Tighten Adjust Bleed air Replace Replace Repair or replace Tighten or replace Replace PageISection section B N-25 N- 9 N- 9 25UONX41 AIR BLEEDING 1. Check the fluid level. (Refer to page N-22.) 2. Turn the steering wheel fully to the left and right several times with the engine not running. 3. Recheck the fluid level. If it has dropped, add fluid. 4. Repeat steps 2 and 3 until the fluid level stabilizes. 5. Start the engine and let it idle. 6. Turn the steering wheel fully to the left and right several times. 7. Verify that the fluid is not foamy and that the fluid level has not dropped. 8. Add fluid if necessary, and repeat steps 6 and 7. Gartner Banana

N ENGINE SPEED SENSING POWER STEERING Caution Never hold the steering wheel to the extreme left or right for more than five seconds with the engine running. This could damage the power steering d pump- 8. Turn the steering wheel fully to the left and right and measure the fluid pressure generated by the gear hous- ing. If the pressure is not within specification, replace the gear housing assembly. Gear housing fluid pressure: 7,601--8,335 kPa (77.545.0 kgflcm2, 1,103-1,208 psi) 9. Remove the gauge set. Install and tighten the pressure hose to the specified torque. Tightening torque: 3247 N.m (3.24.8 kgf.m, 24--34 ft.lbf} 10. Bleed the air from the system. (Refer to page N-21.) STEERING WHEEL AND COLUMN Obtain the code number and deactivate the audio anti- theft system before disconnecting the battery. (Refer to section T.) On-vehicle Inspection -1 Steering wheel effort 1. With the vehicle on a hard, level surface, put the wheels in the straight-ahead position. 2. Start the engine and warm the power steering fluid to 50--60°C (1 22-1 40°F). 3. With the engine running at idle, attach a pull scale to the outermost point of the steering wheel spoke. Then, starting with the wheels in the straight-ahead posi- tion, measure the effort required to turn the steering wheel to the left and to the right. Steering wheel effort: 2635 N (2.63.6 kgf, 5.3-7.9 Ibf) (during one turn of the steering wheel) 2 4. If not within specification, check the following: fluid level, air in system, fluid leakage at hose or connections, func- tion of oil pump and steering gear, and tire pressure. Gartner Banana

ENGINE SPEED SENSING POWER STEERING N STEERING GEAR AND LINKAGE Removal / Installation 1. Turn the wheels to the straight-ahead position. 2. Loosen the wheel lug nuts. 3. On level ground, jack up the front of the vehicle and support it on safety stands. 4. Remove the wheels. Note Turning the steering wheel while the steering gear is removed will make reinstallation difficult. Do not turn the steering wheel while the steering gear is removed. If the steering wheel is turned in that condi- tion, the clockspring connector may have to be adjusted. (Refer to section T.) 5. Remove in the order shown in the figure, referring to Removal Note. 6. With the wheels in the straight-ahead position, install in the reverse order of removal. 7. Tighten all necessary bolts and nuts to the specified torque. 8. After installation: (1) Check for fluid leakage. (Refer to page N-22.) (2) Bleed air from the system. (Refer to page N-21.) (3) Adjust the front wheel alignment. (Refer to section R.) 1. Cotter pin 5. Pressure pipe 2. Nut ~emovai Note ............... page N-26 3. Tie-rod endlsteering knuckle 6. Return hose Removal Note ............... page N- 7 7. Mounting bracket bolt 4. Bolt 8. Steering gear and linkage Gartner Banana

N ENGINE SPEED SENSING POWER STEERING 7. Attach the SST to the pinion and install the plug assem- bly. Adjusting cover 1. Tighten the mounting bracket in a vise. 2. Set the rack to the center position. 3. Tighten the adjusting cover to 4.9 N.m (50 kgf.cm, 43 in4bf) with the SST three times, then return it 25". 4. Apply sealant to the threads of the locknut. 5. Attach the locknut. 6. Measure the pinion torque by using the SST and a pull scale. Standard Center of rack + 90": 1 .O-1 .I N-m {I 0-1 2 kgf-cm, 8.7-1 0.4 in-lbf) ii Scale reading: 1 .&I .2 kg (2.2-2.64 Ib) 7. If not within specification, repeat steps 3 through 6. 8. Install the locknut. Tightening torque: 59-74 N.m (6.0-7.5 kgf.m, 44--54 ftdbf) Hermetic sealing inspection 1. Connect the SST to the power cylinder section of the gear housing. 2. Apply 53.3 kPa (400 mmHg, 15.7 inHg) vacuum with a vacuum pump and verify that it is held for at least 30 seconds. 3. If the vacuum is not held, replace the oil seal. Tie rod 1. Secure the rack gear in a vise, and tighten the tie rods with the wrench. Tightening torque: 79-98 N.m (8.0-10.0 kgf-m, 58-72 ft-lbf) 2. Align the washer with the rack groove, and crimp the washer. Gartner Banana

Before beginning any service procedure. refer to section T of this manual for air bag system service warnings and audio antitheft system alarm conditions . BRAKING SYSTEM INDEX ....................................... P- 2 OUTLINE ..................................... P- 4 SPEClFlCATlONS ........................... P- 4 BRAKE SYSTEM ............................. P- 5 PREPARATION ............................. P- 5 TROUBLESHOOTING GUIDE ................ P- 6 AIR BLEEDING ............................. P- 7 BRAKE HYDRAULIC LINE ................... P- 7 BRAKE FLUID .............................. P- 8 ............................. BRAKE PEDAL P- 9 MASTER CYLINDER (STANDARD) ............ P-11 MASTER CYLINDER (ABS) .................. P-14 POWER BRAKE UNIT ....................... P-20 PROPORTIONING BYPASS VALVE ........... P-23 FRONT BRAKE (DISC) ...................... P-25 CALIPER ................................... P-28 REAR BRAKE (DISC) ........................ P-29 CALIPER ................................... P-32 PARKING BRAKE SYSTEM .................... P-34 TROUBLESHOOTING GUIDE ................ P-34 PARKING BRAKE LEVER .................... P-34 PARKING BRAKE CABLE .................... P-36 ANTILOCK BRAKE SYSTEM (ABS) ............ P-37 DESCRIPTION .............................. P-37 PREPARATION ............................. P-37 TROUBLESHOOTING GUIDE ................ P-38 CIRCUIT DIAGRAM ......................... P-52 HYDRAULIC UNIT ........................... P-53 ........................ ABS CONTROL UNIT P-55 RELAYS .................................... P-56 ABS WHEEL SPEED SENSOR (FRONT) ....... P-58 ABS SENSOR ROTOR (FRONT) .............. P-59 ABS WHEEL SPEED SENSOR (REAR) ........ P-60 ABS SENSOR ROTOR (REAR) ............... P-61 25UOPX-001 Gartner Banana

BRAKE SYSTEM TROUBLESHOOTING GUIDE Problem Poor braking Brakes pull to one side Brakes do not release Pedal goes too far (Too much pedal stroke) Abnormal noise or vibra- tion durlng braking Possible cause Leakage of brake fluid Air in lines Worn pad Brake fluid, grease, oil, or water on pad Hardening of pad surface or poor contact Malfunction of disc brake piston Malfunction of master cylinder Malfunction of power brake unit Malfunction of check valve (vacuum hose) Damaged vacuum hose Deterioration of flexible hose Malfunction of proportioning bypass valve (PBV) Worn pad Brake fluid, grease, oil, or water on pad Hardening of pad surface or poor contact Abnormal wear, distortion, or eccentricity of disc Malfunction of automatic adjuster in rear brake Looseness or deformation of dust cover mounting bolt Malfunction of disc brake piston Worn or improperly adjusted wheel bearing preload lmproper adjustment of wheel alignment Unequal tire air pressure No brake pedal play lmproper adjustment of push rod clearance Clogged master cylinder return port Pad not returning properly lmproper return of malfunction of brake caliper piston Excessive runout of disc plate lmproper adjustment of wheel bearing preload Air in system because of insufficient brake fluid lmproper adjustment of pedal play Worn pad Air in lines Worn pad Deterioration of pads Brakes do not release Foreign material or scratches on disc plate contact surface Looseness of caliper mounting bolt(s) Damage or deviation of disc contact surface Poor contact of pads Insufficient grease on sliding parts Action Repair Air bleed Replace Clean or replace Grind or replace Replace Repair or replace Repair or replace Repair or replace Replace Replace Replace Replace Clean or replace Grind or replace Repair or replace Repair Tighten or replace Repair or replace Replace or adjust Adjust Adjust Adjust Adjust Clean Repair Replace Replace Adjust or replace Add fluid and bleed air Adjust Replace Bleed air Replace Grind or replace Repair Clean Tighten Replace Repair or replace Apply grease Page - P- 7 P-25,29 P-25,29 P-25,29 P-28,32 P-11, 14 P-22 P-22 P-22 P- 7 P-23,24 P-25,29 P-25,29 P-25,29 section M - section M P-28,32 section M section R section Q P- 9 P-l2,15 - - P-28,32 section M section M P- 7 P- 9 P-25,29 P- 7 P-25,29 P-25,29 - - P-26,30 section M P-25,29 - 15UOPX-00 Gartner Banana

BRAKE SYSTEM P MIRROR AIR BLEEDING The brakes should be bleed whenever a brake line is dis- connected. If a hydraulic line is disconnected at the mas- ter cylinder, start at the slave cylinder farthest from the brake master cylinder, and move to the next closest slave cylinder until all four cylinders have been bled. If the disconnection point is anywhere except the master cylinder, start at the point closest to the disconnection, and move to the next farthest slave cylinder until all four cylinders have been bled. 1. On level ground jack up the vehicle and support it evenly on safety stands. 2. Remove the bleeder cap and attach a vinyl tube to the bleeder screw. 3. Place the other end of the vinyl tube in a clear container. 4. One person should depress the brake pedal a few times, and then hold it in the depressed position. 5. A second person should loosen the bleeder screw, drain out the fluid, and close the screw by using the SST. 6. Repeat steps 4 and 5 until only clean fluid is seen. The reservoir should be kept about 3/4 full during bleeding to prevent air from reentering the lines. 7. Modify the brake pipe tightening torque to allow for a torque wrench-SST combination. (Refer to section GI) "Torque Formulas". 8. Tighten the brake pipe by using SST. 9. Check for correct brake operation. 10. Verify that there is no fluid leakage. Clean away any spilled fluid with rags. 11. After bleeding the air, add brake fluid to the reservoir up to the specified level. BRAKE HYDRAULIC LINE On-vehicle Inspection Check the following and replace parts as necessary. 1. Cracks, damage, and corrosion of the brake hose 2. Damage to the brake hose threads 3. Scars, cracks, and swelling of the flexible hose 4. All lines for fluid leakage Gartner Banana

P BRAKE SYSTEM Removal / Installation 1. When disconnecting the flexible hose and brake line, remove the clip after loosening the flare nut by using the SST. > 2. When connecting the flexible hose, do not over tighten or twist it. 3. Verify that the hose does not contact other parts when the vehicle bounces or when the steering wheel is turned all the way to the left or right. 4. Modify the brake pipe tightening torque to allow for a torque wrench-SST combination. (Refer to section GI) "Torque Formulas". 5. Tighten the flare nut by using the SST. Tightening torque: 13-22 N.m (1 3-2.2 kgf-m, %&-I 6 ft-lbf} 6. Bleed the air from the brake system. BRAKE FLUID Inspection Check the fluid level in the reservoir. It should be between MAX and MIN. If the fluid level is extremely low, check the brake system for leaks. J Fluid specification: FMVSS 11 6: DOT-3 Replacement 1. Follow the procedure outlined in Air Bleeding. (Refer to page P-7.) 2. Continuity air bleeding and replacing the brake fluid until only clean fluid is seen. 3. Fill the reservoir to MAX. Gartner Banana

P BRAKE SYSTEM ADJUSTING BOLT I ADJUSTING BOLT ' CKNUT Removal note Brake pipe Caution . Brake fluid will damage painted surfaces. If brake fluid does get on a painted surface, wipe it off lm- mediately. 1. Modify the brake pipe tightening torque to allow for use of a torque wrench-SST combination. (Refer to section GI) "Torque Formulas'' 2. Disconnect/connect the brake pipe fromlto the master . . cylinder by using the SST. 3. Tighten the brake pipe by using the SST. Tightening torque: 13-22 N-m (1.3-2.2 kgfem, 9.4--16 ft-lbf) Installation note Master cylinder 1. Measure the clearance between the push rod of the power brake unit and the piston of the master cylinder. (1) Place the SST atop the master cylinder. Turn the adjusting bolt until it bottoms in the piston. i (2) Apply 66.7 kPa (500 mmHg, 19.7 inHg} vacuum to the power brake unit with a vacuum pump. (3) Invert the SST used in step 1, and place it on the power brake unit. (4) Measure the clearance between the end of the adjusting bolt and the push rod of the power brake unit. If it is not Omm (0 in}, loosen the push rod locknut and turn the push rod to make the adjustment. Gartner Banana