NO.5 ENGINE STALLS-AFTER START/AT IDLE [L8, LF, L3]


5	ENGINE STALLS-AFTER START/AT IDLE
DESCRIPTION	• Engine stops unexpectedly.
POSSIBLE CAUSE	• A/C system operation is improper • Air leakage from intake-air system parts • Purge solenoid valve malfunction • Improper operation of electronic throttle control system • EGR valve malfunction • No signal from CKP sensor due to sensor, related wire or wrong installation • Vacuum leakage • Engine overheating • Low engine compression • Erratic signal to ignition coil • Poor fuel quality • PCV valve malfunction • Air cleaner restriction • Restriction in exhaust system • Electrical connector disconnection • Open or short circuit in fuel pump body and related wiring harness • No battery power supply to PCM or poor GND • Inadequate fuel pressure • Fuel pump body mechanical malfunction • Fuel leakage from fuel injector • Fuel injector clogging • Ignition coil malfunction • Improper air/fuel mixture ratio control • Improper valve timing • Improper operation variable valve timing control system (LF, L3) • Immobilizer system and/or circuit malfunction • Immobilizer system operating property. (Ignition key is not registered.) • 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.


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 the following conditions appear? • The engine is not completely started. • DTC B1681 is displayed.	Yes	Both conditions appear: Go to Step 3.
1		No	Either or other condition appears: Go to the next step.
2	Does the engine stall after approx. 2 s since the engine is started?	Yes	Go to the next step.
2		No	Immobilizer system is normal. Go to Step 8.
3	Is coil connector securely connected to coil?	Yes	Go to the next step.
3	Is coil connector securely connected to coil?	No	Connect the coil connector securely. Return to Step 2.
4	Turn the ignition switch to the ON position. Does security light flush?	Yes	Go to the next step.
4		No	Inspect the instrument cluster and wiring harness. (See INSTRUMENT CLUSTER INSPECTION.)
5	Connect the WDS or equivalent to the DLC-2 and retrieve DTC. Are any of the following DTCs displayed? DTC B1213, B1342, B1600, B1601, B1602, B1681, B2103, B2431	Yes	Go to the appropriate DTC inspection. (See DTC TABLE [L8, LF, L3].)
5		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.
6		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.
7		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.
8		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.
9		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.
10		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.
11		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.
12		No	Repair or replace for short to power.
13	Verify the following: • Vacuum connection • Air cleaner element • No air leakage from intake-air system • No restriction of intake-air system • Proper sealing of intake manifold and components attached to intake manifold: EGR valve • Ignition wiring • Fuel quality: proper octane, contamination, winter/summer blend • Electrical connections • Smooth operation of throttle valve Are all items normal?	Yes	Go to the next step.
13		No	Service if necessary. Repeat Step 13.
14	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.
14		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
15	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.
15		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
16	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 appropriate DTC inspection. (See DTC TABLE [L8, LF, L3].) 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 • Main relay is stuck open. • Open or short circuit in wiring harness between DLC and PCM terminals 1AM or 1AI • Open or poor GND circuit (PCM terminal 1AZ, 1BB, 1BD,or 1BH) • Poor connection of vehicle body GND
16		No	No DTC is displayed: Go to the next step.
17	Attempt to start engine at part throttle. Does engine run smoothly at part throttle?	Yes	Inspect electronic throttle control system operation. (See Electronic Throttle Control System Inspection
17		No	Go to the next step.
18	Connect the WDS or equivalent to the DLC-2. Access RPM PID. Is RPM PID indicating engine speed during engine cranking?	Yes	Go to the next step.
18		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.
19	Visually inspect CKP sensor and teeth of crankshaft pulley. Are CKP sensor and teeth of crankshaft pulley normal?	Yes	Go to the next step.
19		No	Replace the malfunctioning part.
20	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.
20		No	Repair the wiring harnesses.
21	Perform the spark test. (See Spark Test.) Is strong blue spark visible at each cylinder?	Yes	Go to the next step. If symptoms occurs with the A/C on, go to Step 28.
21		No	Repair or replace the malfunctioning part according to spark test result.
22	Inspect the spark plug condition. 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.
22		No	Install spark plugs on original cylinders. Go to the next step.
23	Remove and shake the PCV valve. Does the PCV valve rattle?	Yes	Go to the next step.
23	Remove and shake the PCV valve. Does the PCV valve rattle?	No	Replace the PCV valve.
24	visually inspect the exhaust system part. Is there any deformed exhaust system part?	Yes	Replace the suspected part.
24		No	Go to the next step.
25	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 with ignition switch ON? (See FUEL LINE PRESSURE INSPECTION [L8, LF, L3].)	Yes	Go to the next step.
25		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. (See FUEL PUMP UNIT REMOVAL/INSTALLATION [L8, LF, L3 2WD].) (See FUEL PUMP UNIT REMOVAL/INSTALLATION [L3 4WD].) High: Replace the fuel pump unit. (See FUEL PUMP UNIT REMOVAL/INSTALLATION [L8, LF, L3 2WD].) (See FUEL PUMP UNIT REMOVAL/INSTALLATION [L3 4WD].)
26	Visually inspect for fuel leakage at fuel injector O-ring and fuel line. Service if necessary. Is fuel line pressure held after ignition switch is turned off? (See FUEL LINE PRESSURE INSPECTION [L8, LF, L3].)	Yes	Go to the next step.
26		No	Inspect the fuel injector. If the fuel injector is normal, replace the fuel pump unit. (See FUEL PUMP UNIT REMOVAL/INSTALLATION [L8, LF, L3 2WD].) (See FUEL PUMP UNIT REMOVAL/INSTALLATION [L3 4WD].)
27	Note • The following test is for stall concerns with the A/C on. If other symptoms exist, go to the next step. Connect pressure gauges to A/C low and high pressure side lines. Turn A/C on and measure low side and high side pressures. Are pressures within specifications? (See REFRIGERANT PRESSURE CHECK.)	Yes	Go to the next step.
27		No	If A/C is always on, go to symptom troubleshooting "No.24 A/C is always on or A/C compressor runs continuously". (See NO.24 A/C IS ALWAYS ON OR A/C COMPRESSOR RUNS CONTINUOUSLY [L8, LF, L3].) For other symptoms, inspect the following: • Refrigerant charging amount • Condenser fan operation
28	Disconnect the vacuum hose between the purge solenoid valve and the intake manifold from purge solenoid side. Plug opening end of vacuum hose. Start the engine. Is the engine stall now eliminated?	Yes	Inspect if purge solenoid valve is stuck open. Inspect evaporative emission control system.
28		No	Go to the next step.
29	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.
29		No	Go to the next step.
30	Inspect the engine condition while tapping EGR valve housing. Does the engine condition improve?	Yes	Replace the EGR valve.
30		No	Go to the next step. (LF, L3) Go to Step 32. (L8)
31	Inspect variable valve timing control system operation. (See Variable Valve Timing Control System Operation Inspection [LF, L3].) Does variable valve timing control function properly?	Yes	Go to the next step.
31		No	Repair or replace the malfunctioning parts according to variable valve timing control system operation inspection results.
32	Is the engine compression correct?	Yes	Inspect the valve timing.
32	Is the engine compression correct?	No	Inspect for cause.
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].)

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NO.5 ENGINE STALLS-AFTER START/AT IDLE [L8, LF, L3]