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RADIATOR RADIATOR 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 the undercover. 4. Remove in the order shown in the figure. 5. Install in the reverse order of removal. 1. Air intake pipe 5. Coolant fan, condenser fan 2. Radiator hose 6. Radiator 3. Coolant reservoir hose Inspection . . . . . . . . . . . . . . . . . . . . . . below 4. Coolant fan motor connector, condenser fan motor connector INSPECTION Check for the following and repair or replace as necessary. 1. Cracks, damage, and water leakage. 2. Bent fins (repair with a screwdriver). 3. Distorted or bent radiator inlet. Steps After Installation 1. Install the undercover. _i 2. Connect the negative battery cable. 3. Fill the radiator with coolant. (Refer to page E-6 for WARNING and procedure.) Gartner Banana
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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
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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
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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
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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
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TROUBLESHOOTING GUIDE Warning Fuel vapor is hazardous. It can very easily ignite, causing serious injury and damage. Always keep sparks and flames away from fuel. Fuel in the fuel system is under high pressure when the engine is not running. 4 Warning Fuel line spills and leaks are dangerous. Fuel can ignite and cause serious injuries or death and damage. Fuel can also irritate skin and eyes. To prevent this, always complete the following "Fuel Line Safety Procedures". 35UOFX-008 F-73 F-73 F-74 Fuel Line Safety Procedures A. Release the fuel pressure before disconnecting a fuel line. 1. Start the engine. u 2. Disconnect the fuel pump relay connector. 3. After the engine stalls, turn the ignition switch to OFF. 4. Reconnect the fuel pump relay connector. B. Avoid leakage. 1. When disconnecting a fuel line hose, wrap a rag around it to protect against fuel leakage. 2. Plug the hose after removal. C. Install hose clamps to secure the fuel pressure gauge connections. Self-Diagnosis Checker does not indicate Diagnostic Trouble Code No. but MIL comes on Self-Diagnosis Checker indicates Diagnostic Trouble Code No, of input device but MIL never comes ON Blower fan operates but no cool air is discharged 32 33 34 Pinching Hose When pinching an air hose or fuel hose with pliers, wrap the hose with a rag to prevent damage. MIL always ON MIL never ON NC does not work Checking ignition spark When checking ignition spark condition, hold the high- tension lead with insulated pliers. Note If a timing light is used to check for spark, some lights do not light at the number 2 and 4 cylinders even if the ignition system is normal. J Gartner Banana
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![MAZDA MX-5 1994 Workshop Manual TROUBLESHOOTING GUIDE IT- MIL ALWAYS ON I ( DESCRIPTION I Self-Diagnosis Checker does not indicate Diagnostic Trouble Code No. but MIL always ON I I - - [TROUBLESHOOTING HINTS] Short circuit in wiring MAZDA MX-5 1994 Workshop Manual TROUBLESHOOTING GUIDE IT- MIL ALWAYS ON I ( DESCRIPTION I Self-Diagnosis Checker does not indicate Diagnostic Trouble Code No. but MIL always ON I I - - [TROUBLESHOOTING HINTS] Short circuit in wiring](/manual-img/28/57072/w960_57072-221.png)
TROUBLESHOOTING GUIDE IT- MIL ALWAYS ON I ( DESCRIPTION I Self-Diagnosis Checker does not indicate Diagnostic Trouble Code No. but MIL always ON I I - - [TROUBLESHOOTING HINTS] Short circuit in wiring harness PCME malfunction ISTEP l INSPECTION I ACTION I 1 STEP 33 Disconnect (1 E) wire from PCME and check if MIL goes off 1 E MIL NEVER ON Ground (1 E) wire at PCME with jumper wire and check if MIL comes on 1 E Self-Diagnosis Checker indicates Diagnostic Trouble Code No. of input device but MIL never ON DEscR~pT~O~ I : Other indicator and warning lamps OK [TROUBLESHOOTING HINTS] Bulb burned out Open circuit in wiring harness PCME malfunction INSPECTION Yes No ACTION c3 If OK, replace PCME page F-143 I Q If not OK, repair PCME connector Replace PCME page F-143 Check for short circuit in wiring between combination me- ter and PCME page F-7 Yes No Check if bulb is OK I I Check connection condition of PCME connector tw page F-144 I r> If OK, repair (1 E) wire between PCME and combination meter as= page F-7 c3 If not OK, replace bulb Section T Gartner Banana
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ENGINE TUNE-UP ENGINE TUNE-UP PREPARATION L" SST r I I 16EOF2-012 BASIC INSPECTION Engine Oil 1. Remove the dipstick and check the engine oil level and condition. 2. Add or change oil as necessary. 49 B019 9AO System Selector Coolant (engine cold) For inspection of ignition timing and idle speed Warning Removing the radiator cap or the coolant drain plug while the engine is running, or when the en- gine and radiator are hot is dangerous. Scalding coolant and steam may shoot out and cause seri- ous injury. It may also damage the engine and cooling system. Turn off the engine and wait until it is cool. Even then, be very careful when remov- ing the cap. Wrap a thick cloth around it and slow- ly turn it counterclockwise to the first stop. Step back while the pressure escapes. When you're sure all the pressure is gone, press down on the cap-still using a cloth-turn it, and remove it. 1. Verify that the coolant level is near the radiator filler neck. 2. Verify that the coolant level on the coolant dipstick is be- tween the F and L marks. 3. Add coolant if necessary. Battery Removing the label on the top of the battery or removing the vent caps will void the battery's warranty. 1. Clean any corrosion on the clamps or battery posts. 2. Verify that the battery top is clean. If necessary, clean with baking soda and water. 3. Verify that cables are in good condition and not frayed or corroded. Repair or replace if necessary. 4. Verify that cable clamps are tight. Note Because this is a maintenance free battery, it is not necessary to check the fluid level. Gartner Banana