NO.6 CRANKS NORMALLY BUT WILL NOT START [MZI-3.7]

id0103d2801200

6 | CRANKS NORMALLY BUT WILL NOT START
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DESCRIPTION | • Starter cranks engine at normal speed but engine will not run. • Refer to symptom troubleshooting “NO.5 ENGINE STALLS-AFTER START/AT IDLE” if this symptom appears after engine stall. • Fuel is in tank. • Battery is in normal condition.
POSSIBLE CAUSE | • Vacuum leakage • Poor fuel quality • Air leakage from intake-air system • Restriction in intake-air system • Disconnected electrical connector • External engine shut-off accessory • Restriction in exhaust system • Throttle valve restriction • No battery power supply to PCM • Open PCM ground or vehicle body ground • PCM DTC is stored. • Erratic signal to PCM ― APP sensor or related circuit malfunction ― TP sensor or related circuit malfunction • Improper operation of drive-by-wire control system • No signal from CKP sensor due to sensor, related wire or incorrect installation • No signal from CMP sensor due to sensor, related wire or incorrect installation • Ignition coil or related circuit malfunction • Fuel leakage from injector • Fuel injector is clogged. • Inadequate fuel pressure ― Open or short circuit in fuel pump body and related wiring harness ― Fuel pump mechanical malfunction ― Fuel line clogged ― Pressure regulator malfunction (built-in fuel pump unit) • Fuel leakage from fuel system • PCV valve malfunction • Purge solenoid valve malfunction • Air leakage in intake air system when the engine runs high speed • Low engine compression • Improper variable valve timing control system operation • Improper valve timing Warning • The following troubleshooting flow chart contains the fuel system diagnosis and repair procedures. Read the following warnings before servicing the fuel system: ― Fuel vapor is hazardous. It can easily ignite, causing serious injury and damage. Always keep sparks and flames away from fuel. ― Fuel line spills and leakage 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 “BEFORE SERVICE PRECAUTION” and “AFTER SERVICE PRECAUTION” described in this manual. (See BEFORE SERVICE PRECAUTION [MZI-3.7].)(See AFTER SERVICE PRECAUTION [MZI-3.7].) Caution • Disconnecting/connecting quick release connector without cleaning it may cause damage to fuel pipe and quick release connector. Always clean quick release connector joint area before disconnecting/connecting, and make sure that it is free of foreign material.

Diagnostic procedure

STEP | INSPECTION | RESULTS | ACTION
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1 | Verify the following: • Vacuum connection • External fuel shut off or accessory (such as kill switch, alarm) • Fuel quality: proper octane, contamination, winter/summer blend • No air leakage from intake-air system • Intake-air system restriction (such as air cleaner element, fresh air duct) • Proper sealing of intake manifold and components attached to intake manifold • Ignition wiring • Electrical connections • Fuses • Smooth operation of throttle valve Are all items normal? | Yes | Go to the next step.
No | Repair or replace the malfunctioning part according to the inspection results. Repeat Step 1.
2 | Turn the ignition switch to the ON position (Engine off). Retrieve any PCM DTCs using the M-MDS. (See ON-BOARD DIAGNOSTIC TEST [MZI-3.7].) Are there any DTCs displayed? | Yes | DTC is displayed: • Go to the appropriate DTC inspection. (See DTC TABLE [MZI-3.7].) Communication error message is displayed: Inspect for the following: • Main relay No.1 is stuck open. • Poor connection of vehicle body ground • Open circuit in wiring harness between main relay No.1 and PCM terminal 1BK or 1BP • Open circuit in wiring harness between main relay No.1 and PCM terminal 1AZ • Open or short circuit in wiring harness between DLC-2 and PCM terminals 1AH or 1AL • Open or poor ground circuit (PCM terminal 1B, 1E, 1J) Repair or replace the malfunctioning part according to the inspection results.
No | No DTC is displayed: • Go to the next step.
3 | Access the following PCM PIDs using the M-MDS: (See ON-BOARD DIAGNOSTIC TEST [MZI-3.7].) • APP1 • APP2 Crank the engine with the accelerator pedal released. Are the PIDs indicating that the accelerator pedal is in the released position? | Yes | Go to the next step.
No | Inspect for the following: • APP sensor (See ACCELERATOR PEDAL POSITION (APP) SENSOR INSPECTION [MZI-3.7].) • Wiring harnesses and connectors for following: ― PCM terminal 1Z—APP sensor terminal A ― PCM terminal 1U—APP sensor terminal B ― PCM terminal 1AD—APP sensor terminal C ― PCM terminal 1AB—APP sensor terminal D ― PCM terminal 1Y—APP sensor terminal E ― PCM terminal 1X—APP sensor terminal F Repair or replace the malfunctioning part according to the inspection results.
4 | Access the PCM PIDs TP1, TP2 using the M-MDS. (See ON-BOARD DIAGNOSTIC TEST [MZI-3.7].) Crank the engine with the accelerator pedal released. Are the TP1, TP2 PID indicates the closed throttle position? | Yes | Go to the next step.
No | Inspect for the following: • TP sensor (See THROTTLE POSITION (TP) SENSOR INSPECTION [MZI-3.7].) • Wiring harnesses and connectors for following: ― PCM terminal 2BO—TP sensor terminal A ― PCM terminal 2BR—TP sensor terminal B ― PCM terminal 2AL—TP sensor terminal C ― PCM terminal 2AP—TP sensor terminal D ― PCM terminal 2Z—TP sensor terminal E ― PCM terminal 2AN—TP sensor terminal F Repair or replace the malfunctioning part according to the inspection results.
5 | Attempt to start the engine at part throttle. Does the engine run smoothly at part throttle? | Yes | Inspect the drive-by-wire control system operation. (See ENGINE CONTROL SYSTEM OPERATION INSPECTION [MZI-3.7].) Repair or replace the malfunctioning part according to the inspection results.
No | Go to the next step.
6 | Visually inspect the exhaust system part. Is there any deformed exhaust system part? | Yes | Repair or replace the malfunctioning part according to the inspection results.
No | Go to the next step.
7 | Access the PCM PID RPM using the M-MDS. (See ON-BOARD DIAGNOSTIC TEST [MZI-3.7].) Is the RPM PID indicating the engine speed during the engine cranking? | Yes | Go to the next step.
No | Inspect for the following: • Open or short circuit in CKP sensor • Open or short circuit in CKP sensor wiring harnesses • Open or short circuit in wiring harness between CKP sensor terminal A and PCM terminal 2V • Open or short circuit in wiring harness between CKP sensor terminal B and PCM terminal 2R Repair or replace the malfunctioning part according to the inspection results. • If CKP sensor and wiring harness are normal, go to the next step.
8 | Inspect the CKP sensor. (See CRANKSHAFT POSITION (CKP) SENSOR INSPECTION [MZI-3.7].) Is the CKP sensor normal? | Yes | Go to the next step.
No | Repair or replace the malfunctioning part according to the inspection results.
9 | Inspect the CMP sensor. (See CAMSHAFT POSITION (CMP) SENSOR INSPECTION [MZI-3.7].) Is the CMP sensor normal? | Yes | Go to the next step.
No | Repair or replace the malfunctioning part according to the inspection results.
10 | Inspect the ignition coil related wiring harness condition (intermittent open or short circuit) for all cylinders. Are wiring harness conditions normal? | Yes | Go to the next step.
No | Repair or replace suspected wiring harness and connector.
11 | Perform the spark test. (See ENGINE CONTROL SYSTEM OPERATION INSPECTION [MZI-3.7].) Is strong blue spark visible at each cylinder? | Yes | Go to the next step.
No | Repair or replace the malfunctioning part according to the inspection results.
12 | Verify the spark plug conditions when the spark plug removed in Step 11. Is the spark plug wet, covered with carbon or grayish white? | Yes | Spark plug is wet or covered with carbon: • Inspect for fuel leakage from fuel injector. Spark plug is grayish white: • Inspect the fuel injector for clogging. Repair or replace the malfunctioning part according to the inspection results.
No | Install the spark plugs on original cylinders. Go to the next step.
13 | Inspect the fuel line pressure. (See FUEL LINE PRESSURE INSPECTION [MZI-3.7].) Is the fuel line pressure correct? | Yes | Go to the next step.
No | Zero or low: • Inspect the following: ― Fuel pump relay ― Fuel pump circuit ― Fuel line for clogging • If there is no malfunction, replace the fuel pump unit. (Fuel pump or pressure regulator malfunction) (See FUEL PUMP UNIT REMOVAL/INSTALLATION [MZI-3.7].) High: • Replace the fuel pump unit. (Pressure regulator malfunction) (See FUEL PUMP UNIT REMOVAL/INSTALLATION [MZI-3.7].)
14 | Visually inspect for fuel leakage at fuel injector, O-ring, and fuel line. Is there any fuel leakage? | Yes | Repair or replace the malfunctioning part according to the inspection results.
No | Go to the next step.
15 | Note • The PCV valve cannot be reassembled once it is removed because the tabs will have bee n broken. Inspect the PCV valve without removing it from the vehicle. Inspect the PCV valve with it installed. (See POSITIVE CRANKCASE VENTILATION (PCV) VALVE INSPECTION [MZI-3.7].) Is the PCV valve normal? | Yes | Go to the next step.
No | Replace the PCV valve. (See POSITIVE CRANKCASE VENTILATION (PCV) VALVE REMOVAL/INSTALLATION [MZI-3.7].)
16 | Disconnect the vacuum hose between purge solenoid valve and intake manifold from purge solenoid side. Plug opening end of vacuum hose. Start the engine. Is the engine stall now eliminated? | Yes | Inspect the following: • If purge solenoid valve is stuck open. • EVAP control system Repair or replace the malfunctioning part according to the inspection results.
No | Go to the next step.
17 | Is air leakage felt or heard at intake-air system components while racing the engine to higher speed? | Yes | Repair or replace the malfunctioning part according to the inspection results.
No | Go to the next step.
18 | Inspect the variable valve timing control system operation. (See ENGINE CONTROL SYSTEM OPERATION INSPECTION [MZI-3.7].) Does the variable valve timing control function properly? | Yes | Go to the next step.
No | Repair or replace the malfunctioning part according to the inspection results.
19 | Is the engine compression correct? | Yes | Inspect the valve timing. Repair or replace the malfunctioning part according to the inspection results.
No | Inspect for cause. Repair or replace the malfunctioning part according to the inspection results.
20 | • Verify test results. ― If normal, return to diagnostic index to service any additional symptoms. (See SYMPTOM DIAGNOSTIC INDEX [MZI-3.7].) ― If malfunction remains, inspect related Service Information and perform repair or diagnosis. • If vehicle is repaired, troubleshooting completed. • If vehicle is not repaired or additional diagnostic information is not available, replace the PCM. (See PCM REMOVAL/INSTALLATION [MZI-3.7].)