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 NO.6 CRANKS NORMALLY BUT WILL NOT START [L8, LF, L3]

NO.6 CRANKS NORMALLY BUT WILL NOT START [L8, LF, L3]


id0103a1801200

6

CRANKS NORMALLY BUT WILL NOT START

DESCRIPTION

• The starter cranks engine at normal speed but the engine will not run.
• Refer to symptom troubleshooting "No.5 Engine stalls" if this symptom appears after engine stall.
• Fuel is in tank.
• Battery is in normal condition.

POSSIBLE CAUSE

• No battery power supply to PCM
• Air leakage from intake-air system
• Open PCM GND or vehicle body GND
• Improper operation of electronic throttle control system
• EGR valve malfunction
• 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
• Low engine compression
• Engine overheating
• Vacuum leakage
• Erratic signal to ignition coil
• Improper air/fuel mixture ratio control
• Poor fuel quality
• PCV valve malfunction
• Restriction in intake-air system
• Restriction in exhaust system
• Disconnected electrical connector
• Open or short circuit in fuel pump body and related wiring harness
• Inadequate fuel pressure
• Fuel pump mechanical malfunction
• Fuel leakage from injector
• Fuel injector is clogged.
• Purge solenoid valve malfunction
• Spark plug malfunction
• Ignition coil malfunction
• Improper variable valve timing control system operation (LF, L3)
• Improper valve timing
• Immobilizer system and/or circuit malfunction (if equipped)
• Immobilizer system operating properly. (Ignition key is not registered.) (if equipped)
• Pressure regulator malfunction (built-in fuel pump unit)
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 REPAIR PROCEDURE [L8, LF, L3].)
(See AFTER REPAIR PROCEDURE [L8, LF, L3].)
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

1
Note
• The following test should be perform for vehicles with immobilizer system. Go to Step 13 for vehicles without immobilizer system.
Connect the WDS or equivalent to the DLC-2.
Do any of the following conditions appear?
• Engine does not completely start.
• DTC B1681 is displayed.
Yes

Both conditions appear:

Go to Step 3.
No

Either or other condition appears:

Go to the next step.
2
Does engine stall after approx. 2 s from when it is started?
Yes
Go to the next step.
No
Immobilizer system is normal.
Go to Step 8.
3
Is the coil connector securely connected to the coil?
Yes
Go to the next step.
No
Connect the coil connector securely.
Return to Step 2.
4
Turn the ignition switch to the ON position.
Does the security light flush?
Yes
Go to the next step.
No
Inspect the instrument cluster and wiring harness.
5
Connect the WDS equivalent to the DLC-2 and retrieve the DTC.
Are any of the following DTCs displayed?
DTC

B1213, B1342 B1600, B1601, B1602, B1681, B2103, B2431

Yes
Go to the appropriate DTC inspection.
No
Go to the next step.
6
Is there continuity between PCM GND terminals 1AZ, 1BB, 1BD, 1BH and GND?
Yes
Go to the next step.
No
Repair or replace for open circuit.
7
Measure voltage between PCM GND terminals 1AZ, 1BB, 1BD, 1BH and coil terminal C.
Is the voltage below 1.0V?
Yes
Go to the next step.
No
Repair or replace for short to power.
8
Turn ignition switch to ON.
Access VPWR PID using the WDS or equivalent. Is the VPWR PID value okay?

Specification

Battery voltage

Yes
Go to the next step.
No
Repair or replace for open circuit between PCM terminal 1BE and battery positive post.
9
Disconnect the coil connector.
Turn ignition switch to ON.
Measure the voltage between coil connector terminal D (harness-side) and GND.
Is there battery voltage?
Yes
Go to the next step.
No
Repair or replace wiring harness between coil connector terminal D and fuse panel.
10
Disconnect the PCM connector with the coil
connector disconnected.
Is there continuity between following circuits?
• Coil terminal A and PCM terminal 1F
• Coil terminal B and PCM terminal 1E
Yes
Go to the next step.
No
Repair or replace open circuit.
11
PCM and coil connectors disconnected.
Is there continuity between following terminals and GND?
• Coil terminal A (harness-side)
• Coil terminal B (harness-side)
Yes
• Repair or replace for short to GND.
No
Go to the next step.
12
PCM and coil connectors disconnected.
Measure voltage between following terminals
and GND.
• PCM terminal 1F (harness-side)
• PCM terminal 1E (harness-side)
Is the voltage below 1.0V?
Yes
Go to the next step.
No
Repair or replace for short to power.
13
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: EGR valve
• Ignition wiring
• Electrical connections
• Fuses
• Smooth operation of throttle valve
Are all items normal?
Yes
Go to the next step.
No
Service if necessary.
Repeat Step 13.
14
Connect the WDS or equivalent to the DLC-2.
Turn the ignition switch to the ON position (Engine off).
Retrieve any DTCs.
Are there any DTCs displayed?
Yes

DTC is displayed:

Go to the appropriate DTC inspection.

Communication error message is displayed:

Inspect for the following:
• Open circuit in wiring harness between main relay and PCM terminal 1BE
• Open circuit in wiring harness between main relay terminal E and PCM terminal 1Q
• Open or short circuit in wiring harness between DLC and PCM terminal 1AM or 1AI
• Main relay is stuck open.
• Open or poor GND circuit (PCM terminal 1AZ, 1BB, 1BD or 1BH)
• Poor connection of vehicle body GND
No

No DTC is displayed:

Go to the next step.
15
Connect the WDS or equivalent to the DLC-2.
Access the APP1 and APP2 PIDs. Crank the engine with accelerator pedal released.
Are the APP1 and APP2 PIDs indicating that the accelerator pedal is in the released position?
Yes
Go to the next step.
No
Inspect for the following:
• APP sensor
• Wiring harnesses and connectors for following:
- PCM terminal 1AS - APP sensor terminal E
- PCM terminal 1AV - APP sensor terminal B
- PCM terminal 1AJ - APP sensor terminal A
- PCM terminal 1AP - APP sensor terminal C
- APP sensor terminal
F - PCM terminal 1AO
- PCM terminal 1AL - APP sensor terminal D
16
Connect the WDS or equivalent to the DLC-2.
Access the TP PID. Crank the engine with accelerator pedal released.
Are the TP PID indicates the closed throttle position?
Yes
Go to the next step.
No
Inspect for the following:
• TP sensor
• Wiring harnesses and connectors for following:
- PCM terminal 2AO - TP sensor terminal B
- PCM terminal 2AK - TP sensor terminal A
- PCM terminal 2AL - TP sensor terminal C
- PCM terminal 2AP - TP sensor terminal D
17
Does the engine start with the throttle valve closed?
Yes
Go to Step 19.
No
Go to the next step.
18
Will the engine start and run smoothly at part throttle?
Yes
Inspect the electronic throttle control system operation.
No
Go to the next step.
19
Connect the WDS or equivalent to the DLC-2.
Access RPM PID.
Is RPM PID indicating the engine speed when cranking the engine?
Yes
Go to the next step.
No
Inspect for the following:
• Open or short circuit in CKP sensor
• Open or short circuit in wiring harness between CKP sensor terminal A and GND
• Open or short circuit in wiring harness between CKP sensor terminal B and PCM terminal 2W
• Open or short circuit in wiring harness between CKP sensor terminal C and PCM terminal 2AQ
• Open or short circuit in CKP sensor wiring harnesses
If CKP sensor and wiring harness are normal, go to the next step.
20
Visually inspect the CKP sensor and teeth of crankshaft pulley.
Are CKP sensor and teeth of crankshaft pulley normal?
Yes
Go to the next step.
No
Replace the malfunctioning part.
21
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 the wiring harnesses.
22
Perform the spark test.
(See Spark Test.)
Is strong blue spark visible at each cylinder?
Yes
Go to the next step.
No
Repair or replace the malfunctioning part according to spark test result.
23
Inspect the spark plug conditions.
Is spark plug wet, covered with carbon or grayish white?
Yes

Spark plug is wet or covered with carbon:

Inspect for fuel leakage from injector.

Spark plug is grayish white:

Inspect the fuel injector for clogging.
No
Install the spark plugs on original cylinders.
Go to the next step.
24
Remove and shake the PCV valve.
Does the PCV valve rattle?
Yes
Go to the next step.
No
Replace the PCV valve.
25
visually inspect the exhaust system part.
Is there any deformed exhaust system part?
Yes
Replace the suspected part.
No
Go to the next step.
26
Install the fuel pressure gauge between the fuel pipe and the fuel distributor.
Short check connector terminal F/P to body GND using a jumper wiring.
Turn the ignition switch to the ON position.
Is fuel line pressure correct when ignition switch is turned on/off five times?
Yes
Go to the next step.
No

Zero or low:

Inspect the fuel pump relay and fuel pump circuit.
Inspect the fuel line for clogging.
If there is no malfunction, replace the fuel pump unit.

High:

Replace the fuel pump unit.
27
Visually inspect the fuel injector O-ring and fuel line for fuel leakage.
Service if necessary.
Is the fuel line pressure held after the ignition switch is turned off?
Yes
Go to the next step.
No
Inspect the fuel injector.
If the fuel injector is normal, replace the fuel pump unit.
28
Disconnect the vacuum hose between the purge solenoid valve and the intake manifold from purge solenoid valve side.
Plug opening end of vacuum hose.
Start the engine.
Is starting condition improved?
Yes
Inspect if the purge solenoid valve is stuck open mechanically.
Inspect the evaporative emission control system.
No
Go to the next step.
29
Is air leakage felt or heard at intake-air system components while racing engine to higher speed?
Yes
Repair or replace the malfunctioning part.
No
Go to the next step.
30
Inspect the engine condition while tapping EGR valve housing.
Is engine condition improved?
Yes
Replace the EGR valve.
No
Go to the next step. (LF, L3)
Go to Step 32. (L8)
31
Inspect the variable valve timing control system operation.
Does variable valve timing control function properly?
Yes
Go to the next step.
No
Repair or replace the malfunctioning part.
32
Is the engine compression correct?
Yes
Inspect the valve timing.
No
Inspect for causes.
33
• Verify test results.
- If normal, return to diagnostic index to service any additional symptoms.
(See ENGINE SYMPTOM TROUBLESHOOTING [L8, LF, L3].)
- 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 [L8, LF, L3].)