coolant MAZDA MX-5 1994 Owner's Guide

THERMOSTAT E THERMOSTAT REMOVAL / INSTALLATION u 1. Disconnect the negative battery cable. 2. Drain the engine coolant. (Refer to page E-5 for WARNING and procedure.) 3. Remove in the order shown in the figure. 4. Install in the reverse order of removal. @) REPLACE TAB MUST BE ASSEMBLED TOWARD THERMOSTAT COVER 1. Thermostat cover 3. Thermostat 2. Thermostat cover gasket Inspection . . . . . . . . . . . . . . . . . . . . . . below INSPECTION 1. Visually check that the thermostat valve is airtight. 2. Place the thermostat and a thermometer in water. 3. Heat the water and check the following: Initial-opening temperature Main: 86.5-89.S°C (1 88--193OF) Sub: 83.5--86.S°C (1 8Sl87OF) Full-open temperature: 100°C (21 2°F) Full-open lift Main: 8.0mm 10.31 in) min. Sub: 1.5mm (0.06 in) min. Steps After installation 1. Connect the negative battery cable. 2. Fill the radiator with coolant. (Refer to page €4 for WARNING and procedure.) u Gartner Banana

WATER PUMP WATER PUMP REMOVAL I INSTALLATION 1. Disconnect the negative battery cable. 2. Drain the engine coolant. (Refer to page E-5 for WARNING and procedure) 3. Remove in the order shown in the figure, referring to Removal Note. 4. Install in the reverse order of removal. 1. Timing belt 4. Water pump Service . . . . . . . . . . . . . . . . . . . . . Section B Inspect for cracks, damaged mounting sur- 2. PIS oil pump face, bearing condition, and leakage. Removal Note . . . . . . . . . . . . . . page E-1 1 If the water pump is damage, replace it. 3. Water hose Do not repair it. 5. Water inlet pipe Gartner Banana

WATER PUMP Stens After Installation 1. connect the neaative batterv cable. Removal Note PIS oil pump 1. Remove the PIS oil pump with the hoses still connected. 2. Position the pump away from the water pump and affix it with wire. 2. Fill the radiator kith coolant: (Refer to page E-6 for WARNING and procedure.) Gartner Banana

COOLANT FAN MOTOR , 45UOEX-022 REPLACEMENT 1. Disconnect the negative battery cable. 2. Remove in the order shown in the figure. 3. Install in the reverse order of removal. COOLANT FAN MOTOR INSPECTION 1. Check that the battery is fully charged. 2. Disconnect the coolant fan motor connector. 3. Connect the battery and an ammeter to the coolant fan motor connector. 4. Verify that current is as specified. Current: below 7.7A 5. If current is not within specification and/or the coolant fan does not turn smoothly, replace the coolant fan motor. 45UOEX-023 1. Air intake pipe 4. Coolant fan motor 2. Coolant fan motor connector 5. Coolant fan cowling 3. Coolant fan Gartner Banana

COOLANT FAN RELAY COOLANT FAN RELAY 2. Apply battery positive voltage between terminals B and D. Check for continuity between terminals A and C. 3. If not as specified, replace the coolant fan relay. 45UOEX-025 INSPECTION 1. Check continuity as shown with an ohmmeter. Terminal A-C B-D Continuity NO Yes 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

PURGE SOLENOID VALVE 7* AlC RELAY COOLANT FAN RELAY CONDENSER FAN RELAY STARTER STEERING PRESSURE SENSOR AIR CONDITIONING SENSOR ... CHECK VALVE FUEL-FILTER (HIGH-PRESSURE SIDE) / CRANKSHAFT POSITION SENSOR HEATED OXYGEN SENSOR ltT=I THREE-WAY CATALYST - REAR WINDOW DEFROSTER SWITCH COMBINATION SrmCH BLOWER SWlTCH STOPLIGHT SWITCH (MT) CLUTCH SWITCH (MT) - NEUTRALSWrrCH (MT) TEN TERMINAL PARWEUTRAL SWITCH (AT) VEHICLE SPEED SENSOR ENGINE COOLAMTEMPERATURE SENSOR EGR SOLENOID VALVE WEM) EGR SOLENOID VALVE (VACUUM) - w TO PCME Gartner Banana

F OUTLINE SPECIFICATIONS Item Specification I Throttle body Throat diameter mm {in) I 55 I2.2) Idle speed rpm Ignition timing BTDC 800-900 (850 -+ 50)[MIb, 750-850 (800 + 50)[ATJe 9"-11" (10" k 1 ")* ~ut~~~ressure kPa {kgf/cm2, psi) 1 46-57 14.9--6.7,6%95) Fuel filter Fuel pump TY pe -- m&e regulator Impeller (in-tank) Low-pressure side Hi~h-pressure side Nylon element Paper element Fuel injector TY pe I High-ohmic Type Regulating pressure kPa {kgf/cm2, psi) Diaphragm 26S314 (2.7--3.2,38--46) ldle Air Control Valve Solenoid resistance n 1 10.7-1 2.3 (at 20°C {M°F)) Type of drive Resistance R Voltage 12-1 6 (at 20°C {68"F)) I Solenoid resistance 1 23-27 (at 20°C (68"FJ) I -- brankshaft position sensor d Air valve Opening temperature I Resistance Below 40°C {I 04°F) TY pe Capacity L {US gal, Imp gal) I 48 {12.7, 10.5) Air cleaner housing Purae solenoid valve Hall effect Engine coolant temperature sensor Free play mm (in) I 1-3 {0.0394.118) Fuel Specification 1 Unleaded regular (RON 87 or higher) Element type I I -. I *... With System Selector (49 B019 9AO) test switch at SELF TEST. 35UOFX-004 Oil permeated Accelerator cable Gartner Banana

OUTLINE F COMPONENT DESCRIPTIONS Component Air cleaner housing Air valve Remark Function Filters air entering throttle body When cold, supplies bypass air into dynamicchamber w Engine speed increased to shorten warm-up period Thermowax type Barometric absolute pressure sensor Detects barometric absolute pressure; sends signal to powertrain control module (engine) 3uilt-in PCME Charcoal canister Clutch switch (MT) Stores gas tank fumes while engine stopped Detects in-gear condition: sends signal to powertrain control module (engine) --- ~witch OFF when clutch pedal released Crankshaft position sen- sor Detects No.1 cylinder TDC; sends signal to powertrain control module (engine) Detects crank angle at 180" intervals; sends signal to powertrain control module (engine) Data link connector Concentrated service connector Concentrated terminals are: 1. CIS on-board diagnosis terminal 2. Initial set terminal 3. Fuel pump check terminal Dynamic chamber Interconnects all cylinders Detects coolant temperature; sends signal to powertrain control module (engine) Recircurates oortion of exhaust aas Engine coolant temperature sensor EGR control valve lnstalled in EGR control valve EGR function sensor Detects EGR control valve operating position; send sig- nal to PCME EGR solenoid valve (vent) Controls vacuum to EGR control valve (vent side) Controlled by duty signal from PCME . - EGR solenoid valve (vac- Controls vacuum to EGR control valve (vacuum side) 0 Controlled by duty signal from PCME uum) Fuel filter Filters particles from fuel Injects fuel into intake port Fuel injector Controlled by signals from powertrain control module (engine) High-ohmic injector 0 Sinale port injector nozzle Fuel pump Provides fuel to fuel injectors 0 operates while engine running lnstalled in fuel tank Fuel pump relay Voltage for fuel pump while engine running Fuel vapor valve Prevents fuel from entering canister during vehicle roll over Heated oxygen sensor Detects oxygen concentration; sends signal to power- train control module (engine) 0 Zirconia ceramic and platinum coating ldle air control valve Controls bypass air amount Controlled by duty signal from powertrain control module (engine) Controls idle-up lnstalled in throttle position sensor lnstalled in ignition coil ldle switch Igniter Detects idle condition; sends signal to PCME Receives spark signal from powertrain control module (engine) and generates high voltage in ignition coil Detects high voltage ignition; sends substitute ignition signal to powertrain control module (engine) Ignition switch (START position) Sends engine cranking signal to powertrain control mod- ule (engine) Intake air temperature sensor Detects intake air temperature: sends signal to powertrain control module (engine) Installed in mass airflow sensor Main relay Supplies electric current to fuel injectors, powertrain control module (engine), etc. Gartner Banana