1994 MAZDA MX-5 sensor

ON-VEHICLE MAINTENANCE B CRANKSHAFT POSITION SENSOR DRIVE GROOVE 45UOBX-04 Removal Note Camshaft pulley 1. Hold the camshaft with a wrench at the cast hexagon. 2. Remove the camshaft pulley lock bolts. 3. Remove the camshaft pulleys. Camshaft 1. Loosen the camshaft cap bolts in two or three steps in the order shown in the figure. 2. Remove the camshaft caps. 3. Remove the camshafts. 4. Remove the camshaft oil seals from the camshafts. HLA Caution The HLA must be reinstalled in the same posi- tions from which they were removed. If they are not, it can cause premature and uneven wear. Note Mark the HLA to show their original positions. Remove the HLA from the cylinder head. Installation Note HLA 1. Apply clean engine oil to the friction surfaces. 2. If the HLA are being reused, install them in the position from which they were removed. 3. Verify that the HLA move smoothly in their bores. Camshaft Note The exhaust camshaft has a groove for the crank- shaft position sensor drive. 1. Apply clean engine oil to the camshaft journals and bear- ings. 2. Install the camshaft in position. Gartner Banana

REMOVAL 6 Removal Note PIS oil pump 1. Remove the PIS oil pump with the hoses still connected. 2. Position the pump away from the engine and affix it with wire. 45UOBX-051 AIC compressor (If equipped) 1. Remove the NC compressor with the hoses still con- nected. 2. Position the compressor away from the engine and affix it with wire. I I 45UOBX-052 Step 2 Disconnect the harness connectors shown in the figure. 6 1. Steering pressure sensor 2. Throttle position sensor 3. Idle air control valve 4. Heated oxygen sensor 5. Ignition coil 6. Crankshaft position sensor 7. Ground 8. Fuel injector 9. Alternator 10. Oil pressure switch 11. Starter Gartner Banana

DISASSEMBLY AUXILIARY PARTS 1. Drain the engine oil. 2. Disassemble in the order shown in the figure. 1. Ignition coil and high-tension lead 2. Crankshaft position sensor 3. Manifold bracket 4. Intake manifold assembly 5. Alternator 6. Alternator bracket 7. Right engine mount 8. Oil filter 9. Oil cooler 10. Oil pressure switch 11. Water outlet pipe 12. Spark plug 13. Dipstick and pipe 14. Engine hanger Gartner Banana

ASSEMBLY Camshaft Note The rear end of exhaust camshaft is grooved for the L/ crankshaft position sensor drive. 1. Apply clean engine oil to the camshaft journals and bear- ings. 2. Install the camshaft in position. CRANKSHAFT POSITION SENSOR DRIVE GROOVE 45UOBX-151 3. Apply silicone sealant to the shaded areas shown in the figure. Do not let any sealant get on the journal surfaces. 4. Install the camshaft caps according to the cap number and arrow mark. 5. Install the camshaft cap bolts, and tighten them in two or three steps in the order shown. Tightening torque: Il.3--14.2 N.m {ll5-l4S kgfem, 100-125 in4bf) ij 6. Apply a small amount of clean engine oil to the lip of a new camshaft oil seal. 7. Push the oil seal slightly in by hand. 8. Using a pipe and hammer, tap the oil seal in evenly until it is flush with the edge of the camshaft cap. Note Oil seal outer diameter: 48mm (1.89 in) Oil seal inner diameter: 34mm (1.34 in) Camshaft Pulley 1. Turn the camshafts until the camshaft dowel pins face straight up. 2. lnstall the camshaft pulleys with the I mark (intake side) or the E mark (exhaust side) straight up. Gartner Banana

B ASSEMBLY BLADE NEW Intake Manifold Assembly 1. Remove all foreign material from the intake manifold contact surface. 2. Install a new gasket and the intake manifold assembly. Tightening torque: 19-25 N.m (1.9-2.6 kgf.m, 14--18 ft.lbf) Manifold Bracket Install the manifold bracket. Tightening torque: 38-51 N.m (3.8-5.3 kgf-m, 28-38 ft.lbf) Crankshaft Position Sensor 1. Apply grease to a new O-ring and the blade. 2. Install the crankshaft position sensor to the rear end of exhaust-side camshaft and hand tighten the installation bolt. -J Ignition Coil and High-tension Lead 1. Install the ignition coil. Tightening torque: 19-25 N.m (1 .%--2.6 kgf.m, 14-18 ftdbf) 2. Connect the high-tension leads. Gartner Banana

B INSTALLATION connect the hoses shown in the figure. Step 3 Connect the harness connectors shown in the figure. CRANKSHAFT POSITION h, / SENSOR a SENSOR PRESSURE SWITCH HEATED OXYGEN 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 . FUEL AND EMISSION CONTROL SYSTEMS INDEX ............................ F- 2 ......................... OUTLINE F- 5 .............. SYSTEM DIAGRAM F- 5 VACUUM HOSE ROUTING DIAGRAM ...................... F- 6 WIRING DIAGRAM ............... F- 7 SPECIFICATIONS ............... F- 8 COMPONENT DESCRIPTIONS ... F- 9 ....... TROUBLESHOOTING GUIDE F- 11 ENGINE CONTROL OPERATION CHART ........................ F- 11 RELATIONSHIP CHART .......... F- 12 USING THIS SECTION ........... F- 13 DIAGNOSTIC INDEX ............. F- 15 SYMPTOM TROUBLESHOOTING . F- 17 PREPARATION ................... F- 75 ............. BASIC INSPECTION F- 75 .................. ADJUSTMENT F- 76 ON-BOARD DIAGNOSIS SYSTEM . . F- 78 DESCRIPTION .................. F- 78 PREPARATION .................. F- 79 DIAGNOSTIC TROUBLE CODE NUMBER ...................... F- 79 ... SWITCH MONITOR FUNCTION F- 95 INTAKE AIR SYSTEM .............. F- 98 COMPONENTS .................. F- 98 SYSTEM OPERATION ............ F-100 THROTTLE BODY ............... F-101 INTAKE MANIFOLD .............. F-102 ACCELERATOR PEDAL AND CABLE ........................ F-103 IDLE SPEED CONTROL SYSTEM ... F-104 DESCRI PTlON .................. F-104 PREPARATION .................. F-105 BAC VALVE ..................... F-105 IDLE AIR CONTROL VALVE ....... F-106 FUEL SYSTEM .................... F-107 DESCRIPTION .................. F-107 PREPARATION .................. F-108 SYSTEM OPERATION ............ F-109 FUEL TANK ..................... F-111 FUEL FILTER .................... F-113 FUEL PUMP .................... F-114 FUEL PUMP RELAY .............. F-117 PRESSURE REGULATOR ........ F-118 FUEL INJECTOR ................ F-119 PRESSURE REGULATOR CONTROL SYSTEM ......................... F-122 PRC SOLENOID VALVE .......... F-123 EXHAUST GAS RECIRCULATION (EGR) ........................... F-124 PREPARATION .................. F-124 .................. DESCRIPTION F-124 SYSTEM OPERATION F-125 ............ EGR SOLENOID VALVE (VACUUM) F-125 EGR SOLENOID VALVE (VENT) ... F-126 ......... EGR FUNCTION SENSOR F-126 ........... EGR CONTROL VALVE F-127 ................ EXHAUST SYSTEM F-128 .................. COMPONENTS F-128 OUTLINE OF EMISSION CONTROL ......................... SYSTEM F-129 ............. STRUCTURAL VIEW F-129 POSITIVE CRANKCASE VENTILATION ................... (PCV) SYSTEM F-130 ' DESCRIPTION .................. F-I ..................... PCV VALVE F-1 ..... FUEL EVAPORATIVE SYSTEM F- .................. DESCRIPTION F- ....... PURGE SOLENOID VALVE F- ........ TWO-WAY CHECK VALVE F- ...... THREE-WAY CHECK VALVE F- ............. FUEL VAPOR VALVE F- .......... CHARCOAL CANISTER F- CATALYTIC CONVERTER SYSTEM . F- .................. DESCRIPTION F- .......... THREE-WAY CATALYST F- AIC CUT-OFF CONTROL SYSTEM . . F- .................. DESCRIPTION F- ........... SYSTEM INSPECTION F- ...................... A/c RELAY F-1 36 ..... DECHOKE CONTROL SYSTEM F-137 .................. DESCRIPTION F-137 ......... COOLANT FAN CONTROL F-138 ....................... OUTLINE F-138 .................. COOLANT FAN F-139 ............... CONDENSER FAN F-139 ........... SYSTEM INSPECTION F-140 ........... COOLANT FAN RELAY F-140 ........ CONDENSER FAN RELAY F-140 ............... CONTROL SYSTEM F-141 .................. PREPARATION F-141 ............. STRUCTURAL VIEW F-142 POWERTRAIN CONTROL MODULE .............. (ENGINE) (PCME) F-143 ........ MASS AIRFLOW SENSOR F-152 CRANKSHAFT POSITION SENSOR F-153 ENGINE COOLANT TEMPERATURE ...................... SENSOR F-154 THROTTLE POSITION SENSOR . . F-154 HEATED OXYGEN SENSOR ...... F-156 MAIN RELAY .................... F-157 ............... CLUTCH SWITCH F-157 NEUTRAL SWITCH .............. F-157 STEERING PRESSURE SENSOR . F-158 45UOFX-001 Gartner Banana

INDEX 10. Charcoal canister lnspection . . . . . . . . . . . . . . . . . . page F-133 11. Powertrain control module (engine) Removal / Installation . . . . . . . . page F-143 lnspection . . . . . . . . . . . . . . . . . . page F-143 12. Crankshaft position sensor Removal . . . . . . . . . . . . . . . . . . . page F-153 lnspection . . . . . . . . . . . . . . . . . . page F-153 lnstallation . . . . . . . . . . . . . . . . . page F-153 13. Mass airflow sensor System inspection . . . . . . . . . . . page F-152 lnspection . . . . . . . . . . . . . . . . . . page F-152 14. Engine coolant temperature sensor Removal . . . . . . . . . . . . . . . . . . . page F-154 lnspection . . . . . . . . . . . . . . . . . . page F-154 Installation . . . . . . . . . . . . . . . . . page F-154 15. Throttle position sensor lnspection . . . . . . . . . . . . . . . . . . page F-154 Adjustment . . . . . . . . . . . . . . . . . page F-155 Replacement . . . . . . . . . . . . . . . page F-156 16. Heated oxygen sensor lnspection . . . . . . . . . . . . . . . . . . page F-156 Replacement . . . . . . . . . . . . . . . page F-156 17. Main relay lnspection . . . . . . . . . . . . . . . . . . page F-157 18. Clutch switch (MT) lnspection . . . . . . . . . . . . . . . . . . page F-157 Replacement . . . . . . . . . . . . . . . page F-157 19. Neutral switch (MT) lnspection . . . . . . . . . . . . . . . . . . page F-157 Replacement . . . . . . . . . . . . . . . page F-158 20. Steering pressure sensor lnspection . . . . . . . . . . . . . . . . . . page F-158 Replacement . . . . . . . . . . . . . . . page F-158 21. Fuel pump relay lnspection . . . . . . . . . . . . . . . . . . page F-117 Replacement . . . . . . . . . . . . . . . page F-117 22. PRC solenoid valve lnspection (On-vehicle) . . . . . . page F-123 lnspection . . . . . . . . . . . . . . . . . . page F-123 23. EGR solenoid valve (Vacuum) lnspection . . . . . . . . . . . . . . . . . . page F-125 24. EGR solenoid valve (Vent) lnspection . . . . . . . . . . . . . . . . . . page F-126 25. EGR function sensor lnspection . . . . . . . . . . . . . . . . . . page F-126 26. EGR control valve lnspection . . . . . . . . . . . . . . . . . . page F-127 Replacement . . . . . . . . . . . . . . . page F-127 27. NC relay lnspection . . . . . . . . . . . . . . . . . . page F-136 28. Coolant fan relay lnspection . . . . . . . . . . . . . . . . . . page F-140 29. Condenser fan relay lnspection . . . . . . . . . . . . . . . . . . page F-140 Gartner Banana