spark plugs replace MAZDA MX-5 1994 Workshop Manual

Schedule 2 (Unique driving conditions) (AT) Maintenance interval Maintenance item ENGINE Engine oil I R I R I R I R I R I R I R I R I R I R I R I R Engine oil filter Drive belts Number of months or kilometers {miles}, whichever comes first eoilpancapacity: 4.0 L {4.2 US qt, 3.5 Imp qt} Engine oil (Puerto Rico) I I IGNITION SYSTEM Service data and inspection point Months Kilometers (x 1,m) Miles (x 1,000) D-5 Replace every 4,800 km (3,000 miles) or every 3 months I I I I I I I I - - Engine timing belt (California) Spark plugs Page - - Air cleaner element I I FUEL SYSTEM 4 8 5 I F-99 8-1 2 -. . . '21nspect at 96,000 km {60,000 miles}, and again at 144,000 km {90,000 miles) Replace every 168,000 km (1 05,000 miles) - - R*' - 1'1 l Oilfiltercapacity: 0.15 L (0.16 US qt, 0.13 Imp qt} l Cracks or damage l Tension I R 1 Ie2 1 Engine timing belt ~ --- - - l Plug gap: 1 .&I -1 mm (0.040-4.043 in) l Recommended dark ~luas: 8 16 10 D-6 B-6 Replace every 96,000 km (60,000 miles) Idle speed Fuel filter Fuel lines and hoses NGK , BKRGE-11 BKR5E-I 1 12 24 15 IRI I*2 lt2 l Idle speed MT: 800-900 rpm (Neutral) 1 F-76 AT: 75M0 rpm (P range) 16 32 20 I!*'2 1 20 40 25 24 48 30 - Fittings, connections and com~onents for leaks 36 72 45 F-113 F-1 07 Fuel hoses (California) Hose and tube for emission 28 56 35 Cooling system Engine coolant 32 64 40 COOLING SYSTEM Replace every 168,000 km {I 05,000 miles} 1 1*2 48 96 60 40 80 50 I R 44 88 55 l Fittings, connections and components for leaks Fittings and connections F-1 07 - I R l Hoses for cracks or wear l Coolant level - E4 E-5 Gartner Banana

ENGINE TUNE-UP HLA TROUBLESHOOTING GUIDE Problem 1. Noise when engine is started immediately af- ter oil is changed 2. Noise when engine is started after setting approx. one day 3. Noise when engine is started after cranking for 3 seconds or more 4. Noise when engine is started after new HLA is installed 5. Noise continues more than 10 minutes 5. Noise occurs during idle after high speed run- ning Possible Cause Oil leakage in oil passage Oil leakage in HLA Faulty HLA Action Run engine 2000-3000 rpm. If noise stops after 2 second-10 minutes(') HLA is normal. If not, replace HLA. Time required for engine oil to circulate withir engine, includes tolerance for engine oi condition and ambient temperature. Insufficient oil pressure (Refer to page 8-53) Press down HLA by hand. If it does not move, HLA is normal. If it moves, replace HLA. Check oil pressure. If lower than specification, check for cause. Oil pressure; 295-392 kPa I3.0-4.0 kgf/cm2, 43-56 psil-3000 rpm Deteriorated oil Check oil quality. If deteriorated, replace with specified type and amount of oil. Incorrect oil amount IGNITION TIMING, IDLE SPEED Preparation 1. Check the condition of the engine (spark plugs, leaks in hoses, etc.). 2. Make sure all accessories are OFF. 3. Warm up the engine to normal operating temperature. 4. Connect a timing light and a tachometer to the data link connector terminal IG-. When using an externally pow- ered timing light and/or tachometer, connect it to the power connector (Blue: 1 -pin). Measure valve clearance. If more than Omm {0 in}, replace HLA. Check oil level. Drain or add oil as necessary. Caution Grounding the power connector terminal (Blue: 1-pin) will burn out the 20A wiper fuse. 5. Make sure coolant fan does not operate. Gartner Banana

F TROUBLESHOOTING GUIDE INSPECTION Check if battery positive voltage exists at fuel pump connector fuel pump positive terminal with jumper wire connected.(~tep 3 Check for fuel injector operating sound while crank- ing engine Check if battery positive voltage exists at fuel injector connector B terminal wire with ignition switch ON Connect data link connector terminals F/P and GND with jumper wire and check for correct fuel line pres- sure with ignition switch ON page F-110 Fuel Line pressure: 265--314 kPa f2.7-3.2 kgf/crn2, 38-46 psi) Check for correct engine compression Section B Engine compression: 1,255--883 kPa {12.&9.0 kgf/crn2, 182-1 28 psi)-300 rpm Check if spark plugs are OK WEAR AND CARBON BUILDUP BURNS PLUG GAP 1.0-l.lmm DAMAGE AND (0.040-0.043 in) DETERIORATION DAMAGE Try known good PCME and check if condition im- proves page F-144 - Yes - No Yes Yes - No Yes Yes - No - Yes ACTION Check continuity of fuel pump page F-114 Check fuel pump relay page F-117 Go to Step 7 Go to Step 6 Check PCME terminals 2A, 2U, 2V, 2Y and 22 voltages @3F page F-147 Check for open circuit in wiring between main relay and fuel injector page F-7 Go to next step Low pressure Check fuel line pressure while pinching fuel return hose 0 If fuel line pressure quickly increases, check pressure regulator page F-118 0 If fuel line pressure gradually increases, check for clog- ging between fuel pump and pressure regulator If not clogged, check fuel pump maximum pressure page F-115 Go to next step Check engine condition @3F Section B w Worn piston, piston rings or cylinder wall Defective cylinder head gasket w Distorted cylinder head Improper valve seating w Valve sticking in guide Go to next step Repair, clean, or replace Section G Gartner Banana

TROUBLESHOOTING GUIDE INSPECTION Check if PCME terminal voltages are OK (IC, 1 R, IT, 2D, 20 and 2Q) page F-146 :heck for air leakage of intake air system malfunction page F-100 :heck for EGR system malfunction page F-124 Check if mass airflow sensor US page F-152 Check for correct engine compression Section B Engine compression: 1,255-883 kPa j12.8-9.0 kgf/cm2, 182-128 psil-300 rpm Check if spark plugs are OK WEAR AND CARB/ON BUILDUP BURNS PLUG GAP 1 .O-1 .l mm (0.040-4.043 in) DAMAGE AND DETERIORATION DAMAGE - Yes Yes - No Yes - No Yes - No Yes No - Yes - No - ACTION Go to next step Check for cause (Refer to "Check Point for Each Terminal") page F-148 Repair or replace Go to next step Repair or replace Go to next step Go to next step Repair or replace page F-99 Go to next step Check engine condition Section B Worn piston, piston rings or cylinder wall Defective cylinder head gasket Distorted cylinder head Improper valve seating a Valve sticking in guide Go to next step Repair, clean, or replace @a Section G Try known good PCME and check if condition im- 3rOVeS page F-144 Gartner Banana

TROUBLESHOOTING GUIDE INSPECTION ACTION Check if PCME terminal voltages are OK (1 R, 1 T, ZD, 20 and 20) us page F-146 Yes Go to next step Check for cause (Refer to "Check Point for Each Termi- nal") Djp paae F-148 Check if strong blue spark is visible at each discon. nected high-tension lead while cranking engine Yes - No Go to next step Check ignition system (Refer to Troubleshooting "Misfire") Section G Check for EGR system malfunction page F-124 Yes - No Repair or replace Go to next step Check for fuel injector operating sound at each in- Yes Go to Step 10 jector at idle No - Yes Go to Step 9 Check if battery positive voltage exists at fuel injec- tor connector B terminal with ignition switch ON Check if fuel injector resistance is OK page F-119 Resistance: 12-1 6R G If OK, check wiring between injector and PCME page F-7 o If not OK, replace injector L@? page F-119 No - Yes Check wiring between main relay and fuel injector page F-7 Go to next step Check for correct engine compression Section B Engine compression: 1,255-883 kPa I12.8-9.0 kgflcm2, 182-1 28 psi)-300 rpm Check engine condition Section B I Worn piston, piston rings or cylinder wall r Defective cylinder head gasket r Distorted cylinder head r Improper valve seating Valve sticking in guide No - Yes :heck if spark plugs PLUG GAP 1 .O-1 .l mm (0.04+0.043 in} DETERIORATION 30 to next step qepair, clean, or replace Section G Try known good PCME and check if condition im- roves @r page F-144 Gartner Banana

TROUBLESHOOTING GUIDE B ROUGH IDLE - ALWAYS JCRIPTION I Engine vibrates excessively at idle in every condition 'ROUBLESHOOTING HINTS] AirIFuel mixture too lean Air leakage Fuel injection control malfunction Low fuel line pressure Q One or more injectors not operating or clogged O One or more spark plugs not sparking @ Injection timing misadjustment O Low engine compression INSPECTION >heck for correct intake manifold vacuum at idle tacuum: More than 450 mmHg f17.7 inHg} VACUUM GAUGE =heck if air cleaner element is clean page F-76 :heck if "00" is displayed on Self-Diagnosis Check- 3r with ignition switch ON page F-79 SELECTSWA SYSTEM SELECT 1 Sheck switches for correct operation with Self- Diagnosis Checker Monitor Lamp and ignition switch ON SELECT SW A page F-95 Sheck if PCME terminal voltages are OK MONITOR . Sheck i (1 R, IT, 2D, 20 and 2Q) page F-146 - Yes Yes - No - Yes Yes - No - Yes ACTION Go to next step Check for air leakage of intake air system components page F-100 Go to next step Replace air cleaner element page F-99 Go to next step Diagnostic Trouble Code No. displayed Check for cause (Refer to specified check sequence) page F-81 "88" flashes Check PCME terminal 1 E voltage page F-136 Specification: Battery positive voltage (Ignition switch ON) e If OK, replace PCME page F-143 Q If not OK, check wiring between PCME and Self-Diagno- sis Checker page F-7 Go to next step Lamp not ONlOFF with specified switch Check for cause (Refer to specified check sequence) page F-96 Lamp always ON Check wiring between PCME terminal 1 D and Self-Diag- nosis Checker as? page F-7 Go to next step Check for cause (Refer to "Check Point for Each Termi- nal") us ~aae F-148 Gartner Banana

TROUBLESHOOTING GUIDE INSPECTION :heck if spark plugs are OK WEAR AND CARBQN BUILDUP BURNS PLUG GAP 1 .O-1 .l mm DAMAGE AND t0.040--0.043 in) DETERIORATION DAMAGE Try known good PCME and check if condition im- proves as page F-144 Yes ACTION Go to next step Repair, clean, or replace Section G Gartner Banana

TROUBLESHOOTING GUIDE - TEP - 4 INSPECTION ACTION ;heck for correct intake manifold vacuum at idle Yes - No - Yes Go to next step Intake manifold vacuum: More than 450 mmHg I17.7 InHg} ,VACUUM GAUGE Low vacuum Check for air leakage of intake air system page F-100 Zheck for fuel injector operating sound at idle with sound scope or screwdriver Go to Step 7 Go to Step 6 Check if fuel injector resistance is OK us page F-119 Check if battery positive voltage exists at fuel injec- tor connector B terminal Yes - No - Yes - No Resistance: 12-1 6R e If OK, check wiring between PCME and fuel injector page F-7 Q If not OK, replace fuel injector us page F-119 Check wiring between PCME and fuel injector page F-7 Disconnect each fuel injector connector at idle and check if engine speed decreases equally each time Disconnect each high-tension lead at idle and :heck if engine speed decreases equally each time Q If OK, go to Step 9 Q If not OK, check fuel injector for fuel leakage page F-120 Go to step 8 Zheck if spark plugs are OK ILDUP PLUG GAP 1.0-l.lmrn [0.04-.043 in) DAMAGE AND DETERIORATION Check if PCME terminal voltages are OK (1 R, IT, 2Q2Q and 2X) page F-146 Yes - No - Yes Check for correct engine compression Section B + If OK, replace fuel injector page F-119 Q If not OK, check for cause (Refer to Section 6) Section B Repair, clean, or replace Go to next step No - Yes Check for cause (Refer to "Check Point for Each Termi- nal") page F-148 Check purge solenoid valve = page F-132 - - Check if vacuum is felt at purge solenoid valveat Go to next step Try known good PCME and check if condition im- proves page F-144 Gartner Banana

TROUBLESHOOTING GUIDE INSPECTION ACTION ;heck if PCME terminal voltages are OK 1 R, IT, 20.20 and 2Q) page F-146 :heck if strong blue spark is visible at each discon- iected high-tension lead while cranking engine ;heck for fuel injector operating sound at each fuel njector at idle ;heck if battery positive voltage exists at fuel injec- :or connector B terminal :heck if spark plugs are OK PLUG GAP 14-1 .l mm (0.040-4.043 in) DAMAGE AND DETERIORATION :heck for EGR system malfunction uz page F-124 Yes No - Yes - No - Yes No - Yes - No - Yes No - Yes - No - Go to next step Check for cause (Refer to "Check Point for Each Termi- nal") @&T page F-148 Go to next step Check ignition system (Refer to Troubleshooting "Misfire") I@? Section G Go to Step 9 Go to Step 8 Check if fuel injector resistance is OK @&T page F-119 Resistance: 12-1 6R o If OK, check wiring between PCME and fuel injector page F-7 0 If not OK, replace fuel injector @&T page F-119 Check wiring between PCME and fuel injector I@? page F-7 Go to next step Repair or replace Section G Repair or replace Go to next step Gartner Banana

TROUBLESHOOTING GUIDE INSPECTION :heck for correct ignition timing at idle page F-76 gnition timing: 10" .t lo BTDC ;heck if spark plugs are OK RBON BUILDUP PLUG GAP 1 .O-l.lmrn b.040--0.043 in} DAMAGE AND DETERIORATION DAMAGE :heck if resistance of high-tension leads are OK lesistance: 16 k!2 per 1 m (3.28 ft) :heck if resistance of ignition coil is OK Section G lesistance (at 20°C (66°F)): Secondary coil ... 8.7-12.9 'heck for correct engine compression Section B ngine compression: 1,255483 kPa (12.8-9.0 kgf/cm2, 182-128 psiE.300 rpm Yes No Yes No - Yes Yes No - Yes - No ACTION Check if ignition timing advances when accelerating s, If advances, go to next step +, If no advance, replace PCME terminal voltages page F-143 Adjust page F-76 Go to next step Repair, clean, or replace us Section G Go to next step Replace w Section G Go to next step Replace Section G 30 to next step Zheck engine condition w Section B D Worn piston, piston rings or cylinder wall D Defective cylinder head gasket Distorted cylinder head Improper valve seating B Valve sticking in guide Gartner Banana