Engine Controls - Basic Diagnostic Procedures: Other Mazda Millenia I рестайлинг

Compression

Check engine mechanical condition with a compression gauge, vacuum gauge, or an engine analyzer. Ensure oil level and condition are okay. Ensure battery is fully charged. See engine analyzer manual for specific instructions.

COMPRESSION SPECIFICATIONS

Exhaust System Backpressure

Exhaust system can be checked with a vacuum or pressure gauge. Remove Heated Oxygen Sensor (HO2S) or air injection check valve (if equipped). Connect a 0-5 psi pressure gauge and run engine at 2500 RPM. If exhaust system backpressure is greater than 2 psi, exhaust system or catalytic converter is plugged.

If a vacuum gauge is used, connect vacuum gauge hose to intake manifold vacuum port and start engine. Observe vacuum gauge. Open throttle part way and hold steady. If vacuum gauge reading slowly drops after stabilizing, exhaust system should be checked for a restriction.

PRELIMINARY CHECKS

Ensure following systems and components are in good condition and operating properly before diagnosing problems in fuel injection system

1. Battery and charging system condition.
2. All wiring and vacuum connections.
3. Air cleaner and ducting.
4. State of tune.
5. Fuel delivery system.
6. Cooling system.
7. Inertia fuel shutoff switch.
8. Blown head gasket (liquid in cylinder).
9. Fuel tank contents and fuel gauge accuracy.
10. For dirt, water or other contamination in fuel.
11. Fuel lines and fittings for leaks.
12. Fuel delivery system for proper pressure and volume.
13. For inoperative fuel injectors.
14. Check for improperly installed electronic equipment such as anti-theft system, CB radio, cellular telephone or stereo.

Engine Does Not Crank

Check for enabled anti-theft system. Check starting and charging system for correct operation. Check for hydrostatic lock (liquid in cylinder). Repair as necessary.

Engine Cranks But Will Not Start

1. Check fuel tank contents and fuel gauge accuracy. Check for dirt, water or contamination in fuel.
2. Check fuel lines and fittings for leaks. If no leaks are found, check fuel delivery system for proper pressure and volumes. Reset Inertia Fuel Shutoff (IFS) switch (if necessary).
3. Check for damaged or contaminated fuel injector wiring harness and connector. Ensure fuel injectors pulse when engine is cranked.
4. Check ignition system for strong spark at spark plugs. If spark is not present or if spark is weak, proceed as follows: On all EEC-V models, go to TEST JE in appropriate SELF-DIAGNOSTICS article. On all others, go to appropriate SELF-DIAGNOSTICS article.

Except B2300, B2500, B3000, B4000 & Tribute

Disconnect fuel pump relay. See FUEL PUMP RELAY LOCATIONS table. Start engine (if possible) and allow to die. Turn ignition off. Reconnect fuel pump relay.

FUEL PUMP RELAY LOCATIONS

Fuel Line Pressure

1. Disconnect negative battery cable. Install fuel pressure gauge in fuel supply line. Reconnect negative battery cable. Locate data link connector in left side of engine compartment. Connect a fused jumper wire between data link connector terminals F/P and GND. see scheme 1 Turn ignition on and observe fuel line pressure. See «FUEL LINE PRESSURE»(ref-11545-S22095565452000111700000) table.
2. If fuel line pressure is high, check for plugged return line. If no problem is found, replace fuel pressure regulator. If fuel line pressure is low, check fuel pump maximum pressure. See «FUEL PUMP MAXIMUM PRESSURE»(ref-11545-S14146375932000111700000). If fuel pump maximum pressure is as specified, check for plugged or restricted fuel line or fuel filter. Repair as necessary. If no problems are found, check pressure regulator hold pressure. See «FUEL PRESSURE REGULATOR HOLD PRESSURE»(ref-11545-S12773970352000111700000).

FUEL LINE PRESSURE

Fuel Pump

1. Fuel pump is located inside fuel tank. Locate data link connector in left side of engine compartment. Connect a fused jumper wire between data link connector terminals F/P and GND. see scheme 1 Remove fuel filler cap. Turn ignition on. Listen for fuel pump operation at fuel filler pipe. Install fuel filler cap.
2. If fuel pump does not operate, using DVOM, measure voltage between fuel pump connector power terminal and chassis ground. If battery voltage is present, go to next step. If battery voltage is not present, repair power circuit to fuel pump. See WIRING DIAGRAMS article.
3. Using DVOM, check for continuity between fuel pump connector ground terminal and chassis ground. If continuity is present, replace fuel pump. If continuity is not present, repair ground circuit.

Fuel Pump Hold Pressure

1. Disconnect negative battery cable. Disconnect fuel inlet hose at fuel rail. Install fuel pressure gauge to fuel inlet hose and plug fuel pressure gauge outlet hose. Reconnect negative battery cable.
2. Locate data link connector in left side of engine compartment. Connect a fused jumper wire between data link connector terminals F/P and GND. see scheme 1 Turn ignition on for 10 seconds to operate fuel pump. Turn ignition off and disconnect fused jumper wire. Wait 5 minutes and observe fuel pressure. See «FUEL PUMP HOLD PRESSURE»(ref-11545-S38744672562001061400000) table. On all models, if fuel pressure is not as specified, replace fuel pump.

FUEL PUMP HOLD PRESSURE

Fuel Pump Maximum Pressure

1. Disconnect negative battery cable. Disconnect fuel inlet hose at fuel rail. Install fuel pressure gauge to fuel inlet hose and plug fuel pressure gauge outlet hose. Reconnect negative battery cable.
2. Locate data link connector in left side of engine compartment. Connect a fused jumper wire between data link connector terminals F/P and GND. see scheme 1 Turn ignition on for 10 seconds to operate fuel pump and observe fuel pressure. See «FUEL PUMP MAXIMUM PRESSURE»(ref-11545-S33815027302000111700000) table. Turn ignition off and disconnect fused jumper wire. If fuel pressure is not as specified, replace fuel pump.

FUEL PUMP MAXIMUM PRESSURE

Fuel Pump Relay

1. Locate fuel pump relay. See «FUEL PUMP RELAY LOCATIONS»(ref-11545-S08256602552000111700000) table under FUEL PRESSURE RELEASE. Using fused jumper wires, connect battery voltage to fuel pump relay terminal "A" (positive) and terminal "B" (negative). (Scheme 1)or (Scheme 2).
2. On Miata and MPV, check continuity between fuel pump relay terminals "C" and "E". On Millenia, Protege and 626, check continuity between fuel pump relay terminals "C" and "D". On all models, with battery voltage connected, continuity should be present. With battery voltage disconnected, continuity should not be present. If continuity is not as specified, replace fuel pump relay.

Scheme 1

Scheme 2

Fuel Pressure Regulator

1. Disconnect negative battery cable. Install fuel pressure gauge in fuel supply line. Reconnect negative battery cable.
2. Start and operate engine at idle. Ensure vacuum is available to pressure regulator. Observe fuel pressure with vacuum hose connected and disconnected at fuel pressure regulator. See «REGULATED FUEL PRESSURE»(ref-11545-S24222926982000111700000) table. If fuel pressure is not as specified, check fuel pressure regulator hold pressure. See «FUEL PRESSURE REGULATOR HOLD PRESSURE»(ref-11545-S12773970352000111700000) .

REGULATED FUEL PRESSURE

Fuel Pressure Regulator Hold Pressure

1. Disconnect negative battery cable. Install fuel pressure gauge in fuel supply line. Reconnect negative battery cable.
2. Locate data link connector in left side of engine compartment. Connect a fused jumper wire between data link connector terminals F/P and GND. see scheme 1 Turn ignition on for 10 seconds to operate fuel pump. Turn ignition off and disconnect fused jumper wire. Wait 5 minutes and observe fuel pressure.
3. Fuel pressure should be more than 21 psi (1.5 kg/cm 2 ). If fuel pressure is not as specified, replace fuel pressure regulator.

Injector Fuel Leakage

1. Using mechanics wire, secure each fuel injector to fuel rail. Disconnect fuel injector connectors. Remove fuel rail assembly from intake manifold. See REMOVAL, OVERHAUL & INSTALLATION article. Reconnect fuel lines to fuel rail. Locate data link connector in left side of engine compartment.
2. Connect a fused jumper wire between data link connector terminals F/P and GND. see scheme 1 Turn ignition on. Tilt injectors about 60 degrees and check injector nozzles for fuel leaks. Fuel leakage should be less than one drop every 2 minutes. If fuel leakage is present, replace injector.

FUEL PRESSURE (B2300, B2500, B3000, B4000 & TRIBUTE)

1. Release fuel pressure. Install fuel pressure gauge. Turn ignition on and read fuel pressure. Compare fuel pressure reading on fuel pressure gauge with specifications in «FUEL PRESSURE SPECIFICATIONS»(ref-11545-S08592932992000111700000) table.
2. If fuel pressure is not within specifications, check fuel pressure regulator. With engine running, connect hand vacuum pump and apply vacuum to regulator.
3. Ensure fuel pressure changes as vacuum at regulator is increased and decreased. If no pressure change occurs, replace regulator and recheck system. For additional testing information, go to TEST HC in appropriate SELF-DIAGNOSTICS article.

FUEL PRESSURE SPECIFICATIONS (1)

IGNITION CHECKS

Note. Perform following tests in sequence shown, unless test procedures indicate otherwise. For the following test, the term Electronic Ignition (EI) may be used to describe the ignition system.

Spark Check

Remove spark plug. Connect spark plug to high-tension lead and hold about 1/4" from ground. Crank engine and verify a strong Blue spark is discharged. If spark is not present, measure spark plug wire resistance on suspect wire. Resistance should be less than 16,000 ohms per 3.28 feet. Replace spark plug wire and spark plug as necessary.

Camshaft Position Sensor (Miata)

1. Remove and inspect Camshaft Position (CMP) sensor. Clean off any metal particles or shavings. Reinstall sensor.
2. Connect scan tool. Start engine. Using scan tool, enter vehicle info and connect scan tool leads to PCM. See «CMP/PCM TERMINAL IDENTIFICATION (MIATA & PROTEGE)»(ref-11545-S33304006472001061500000) table. Select DIGITAL MEASUREMENT SYSTEM, then FREQUENCY METER. Press link key to select RPM PID. Select PID/DATA MONITOR, then PCM. Press START.
3. Frequency meter should be displayed. Ensure threshold voltage is 2 volts and DC voltage is selected. Frequency should match specifications. See «CMP FREQUENCY SPECIFICATIONS (MIATA & PROTEGE 1.6L)»(ref-11545-S17086154702001061500000) table.
4. Change scan tool threshold voltage to 6 volts. Ensure frequency is 0 Hz. If frequency is out of specifications, check wiring for open or short circuit. Check camshaft pulley for damage. Repair as necessary.

CMP/PCM TERMINAL IDENTIFICATION (MIATA & PROTEGE)

CMP FREQUENCY SPECIFICATIONS (MIATA & PROTEGE 1.6L)

Camshaft Position Sensor (Millenia 2.3L)

Camshaft Position (CMP) sensor is located on right front of engine. Disconnect CMP sensor harness connector. Check for continuity between CMP sensor connector terminals "B" and "C". If continuity is present, replace CMP sensor. If continuity is not present, repair wire harness.

Camshaft Position Sensor (Millenia 2.5L)

Camshaft Position (CMP) sensor is located inside of distributor and is an integrated part. Disconnect distributor 6-pin harness connector. Check for continuity between distributor connector terminals "B" and "D". If continuity is present, replace distributor. If continuity is not present, repair wire harness as necessary.

Camshaft Position Sensor (MPV)

1. Disconnect Camshaft Position (CMP) sensor connector. Measure resistance between CMP sensor connector terminals. If resistance is 292-385 ohms, go to next step. If resistance is not 292-385 ohms, replace sensor.
2. Disconnect PCM harness connector. Connect breakout box to PCM harness connector. Leave PCM disconnected. Check continuity of following circuits: Between CMP sensor harness connector terminal No. 1 (Blue wire) and PCM harness connector terminal No. 85 (Orange wire). Between CMP sensor harness connector terminal No. 2 and PCM harness connector terminal No. 86 (Yellow wire). Repair as necessary.

Camshaft Position Sensor (Protege 1.6L)

1. Remove and inspect Camshaft Position (CMP) sensor. Clean off any metal particles or shavings. Reinstall sensor.
2. Remove PCM and install 104 pin breakout box.
3. Connect scan tool to DLC-2. Connect test leads to breakout box terminals. See «CMP/PCM TERMINAL IDENTIFICATION (MIATA & PROTEGE)»(ref-11545-S33304006472001061500000) table.
4. Start engine. Monitor RPM PID. Inspect frequency value at specified RPM PIDs. See «CMP FREQUENCY SPECIFICATIONS (MIATA & PROTEGE 1.6L)»(ref-11545-S17086154702001061500000) table. Threshold voltage should be 2 V DC.
5. Change threshold voltage to 6 V DC. Ensure frequency indicates 0 Hz. If frequency value or breakout box terminal No. 85 voltage are out of specifications, check for short or open in following circuits: Open between CMP sensor harness connector terminal "B" and PCM harness connector terminal No. 85 (Blue wire). Open between CMP sensor harness connector terminal "A" and main relay harness connector terminal "D" (White/Red wire). Open between CMP sensor harness connector terminal "C" and PCM harness connector terminal No. 103 (Black/Red wire). Short to ground between CMP sensor harness connector terminal "B" and PCM harness connector No. 85 (Blue wire). Short to ground between CMP sensor harness connector terminal "A" and main relay harness connector terminal "D" (White/Red wire). Reconnect connectors and check camshaft pulley (exhaust side) for damage or cracks. Repair or replace as necessary.

Camshaft Position Sensor (Protege 2.0L)

1. Disconnect Camshaft Position (CMP) sensor connector. CMP sensor is located near front of valve cover. Using ohmmeter, measure resistance between CMP sensor connector terminals. Resistance should be 950-1250 ohms. Replace as needed.
2. If sensor is okay, disconnect PCM harness connector and check for open or short in following circuits: Between CMP sensor harness connector terminal "A" and PCM harness connector terminal No. 85 (Blue wire). Between CMP sensor harness connector terminal "B" and PCM harness connector terminal No. 86 (Green wire). Repair as necessary.

Camshaft Position Sensor (626 2.0L)

Disconnect Camshaft Position (CMP) sensor harness connector. CMP sensor is located on timing belt cover, at upper front of engine. Using ohmmeter, measure resistance between component terminals. Resistance should be 950-1250 ohms. Replace as needed.

Camshaft Position Sensor (626 2.5L)

Disconnect Camshaft Position (CMP) sensor harness connector. CMP sensor is located next to right timing pulley. Using ohmmeter, measure resistance between CMP sensor harness connector terminals "A" and "B". Resistance should be approximately 550 ohms. Replace as needed.

Crankshaft Position Sensor Resistance

Disconnect Crankshaft Position (CKP) sensor connector. Using ohmmeter, measure resistance between terminals "A" and "B". (Scheme 3) Resistance should be as specified. See CRANKSHAFT POSITION SENSOR RESISTANCE table. If resistance is not as specified, replace crankshaft position sensor.

CRANKSHAFT POSITION SENSOR RESISTANCE

Scheme 3

Crankshaft Position Sensor Air Gap

Using a feeler gauge, measure air gap between crankshaft pulley and Crankshaft Position (CKP) sensor. (Scheme 4) If air gap is not.020-.060 In.(.5-1.5 mm), replace crankshaft pulley or CKP sensor. On Miata, CKP sensor is adjustable. If sensor will not adjust, replace CKP sensor or plate behind crankshaft pulley.

Scheme 4

Ignition Coil Power Source (Miata & Protege)

Turn ignition on. Using voltmeter, check for 12 volts between ground and ignition coil terminals 1A and 2A. (Scheme 5) If voltage is not present, check battery feed, main fuse, ignition switch and fusible links. See WIRING DIAGRAMS article.

Ignition Coil Power Source (Millenia)

Turn ignition on. Using voltmeter, on 2.3L, check for 12 volts at ignition coil 4-pin harness connector terminal (Black/White wire) and ground. On 2.5L check for 12 volts between distributor terminal 2A and ground. If voltage is not present, check battery feed, main fuse, ignition switch and fusible links. See WIRING DIAGRAMS article.

Ignition Coil Power Source (626 2.0L & 2.5L)

Turn ignition on. Using voltmeter, on 2.0L, check for 12 volts between ignition coil terminal "B" and ground. On 2.5L, check for 12 volts between ignition coil terminal "D" and ground. If voltage is not present, check battery feed, main fuse, ignition switch and fusible links. See WIRING DIAGRAMS article.

Ignition Coil Resistance (Miata & Protege)

Using an ohmmeter, measure secondary resistance between coil towers No. 1 and 4 and between coil towers No. 2 and 3. (Scheme 6) Resistance should be as specified. See IGNITION COIL RESISTANCE table. If resistance is not as specified, replace appropriate coil.

IGNITION COIL RESISTANCE (1)

Scheme 5

Scheme 6

Ignition Coil Resistance (Millenia 2.3L)

Ignition coil and ignition control module are integrated as a coil on plug unit. Ignition coil testing procedure and resistance specifications are not available from manufacturer. If misfire DTC is present (DTC's P0300-P0306), refer to appropriate Self-Diagnostics article to retrieve codes and diagnose misfire. Misfire diagnostic procedure includes switching ignition coil with a known good ignition coil from another cylinder.

Ignition Coil Resistance (Millenia 2.5L)

1. Disconnect 3-pin harness connector. Using ohmmeter, measure primary resistance between terminals "A" and "B". (Scheme 7) Resistance should be as specified. See «IGNITION COIL RESISTANCE»(ref-11545-S05854320042000111700000) table. If resistance is not as specified, replace distributor.
2. Using an ohmmeter, measure secondary resistance between terminal "A" and coil tower. (Scheme 8) Resistance should be as specified. See «IGNITION COIL RESISTANCE»(ref-11545-S05854320042000111700000) table. If resistance is not as specified, replace distributor.

Scheme 7

Scheme 8

Ignition Coil Resistance (MPV)

1. Disconnect 4-pin connector. Using ohmmeter, measure primary resistance between terminals "A" and "D", terminals "B" and "D", and terminals "C" and "D". (Scheme 9) Resistance should be as specified. See «IGNITION COIL RESISTANCE»(ref-11545-S05854320042000111700000) table. If resistance is not as specified, replace coil.
2. Using an ohmmeter, measure secondary resistance between coil towers No. 1 and 5, towers No. 2 and 6, and towers No. 3 and 4. See «IGNITION COIL RESISTANCE»(ref-11545-S05854320042000111700000) table. If resistance is not as specified, replace coil.
3. Measure resistance between terminal "D" and coil case. Resistance should be greater than 10-megohms. If resistance is not as specified, replace coil.

Scheme 9

Ignition Coil Resistance (626 2.0L & 2.5L)

1. Disconnect ignition coil harness connector. Using ohmmeter, on 2.0L, measure primary resistance between ignition coil terminals "A" and "B" and terminals "B" and "C". On 2.5L, measure between terminals "A" and "D", terminals "B" and "D" and terminals "C" and "D". (Scheme 10)or (Scheme 11). Resistance should be as specified. See «IGNITION COIL RESISTANCE»(ref-11545-S05854320042000111700000) table. If resistance is not as specified, replace ignition coil.
2. Disconnect high tension leads. Using an ohmmeter, on 2.0L, measure secondary resistance between coil towers No. 1 and 4 and towers No. 2 and 3. On 2.5L, measure secondary resistance between coil towers No. 1 and 4, towers No. 2 and 5 and towers No. 3 and 6. (Scheme 10)or (Scheme 11). Resistance should be as specified. See «IGNITION COIL RESISTANCE»(ref-11545-S05854320042000111700000) table. If resistance is not as specified, replace ignition coil.
3. Measure resistance between terminal "D" and coil case. Resistance should be greater than 10-megohms. If resistance is not as specified, replace coil.

Scheme 10

Scheme 11

Ignition Control Module (Millenia)

Testing information is not available from manufacturer. Check for diagnostic trouble codes. See appropriate SELF-DIAGNOSTICS article.

1. Perform self diagnostic QUICK TEST to check for ignition-related fault codes, and repair as necessary. See QUICK TEST in appropriate SELF-DIAGNOSTICS article. If no fault codes are retrieved, check ignition system wiring harness connectors for corrosion and tight fit. See WIRING DIAGRAMS article. Clean or repair connectors as necessary.
2. If wiring and connectors are okay, use Neon Bulb Spark Tester (D8IP-6666-A) to check for spark at each spark plug wire while cranking engine. If spark is strong and consistent at each spark plug (one spark per crankshaft revolution), ignition system is okay. If spark is not present, go to TEST JD in appropriate SELF-DIAGNOSTICS article.

IDLE SPEED & IGNITION TIMING

Connect scan tool to DLC-2. Ensure idle speed and base ignition timing are set to specification. See IDLE SPEED SPECIFICATIONS and IGNITION TIMING SPECIFICATIONS (Degrees BTDC @ RPM) tables. If adjustment is necessary, see ON-VEHICLE ADJUSTMENTS article.

IDLE SPEED SPECIFICATIONS

IGNITION TIMING SPECIFICATIONS (Degrees BTDC @ RPM)

SUMMARY

If no faults were found while performing BASIC DIAGNOSTIC PROCEDURES, proceed to appropriate SELF-DIAGNOSTICS article. If no hard codes are found in self-diagnostics, proceed to TROUBLE SHOOTING - NO CODES article for diagnosis by symptom (i.e., ROUGH IDLE, NO START, etc.) or intermittent diagnostic procedures.