NO.5 ENGINE STALLS-AFTER START/AT IDLE [SKYACTIV-G 2.5T]

id0103q4801100

5

ENGINE STALLS-AFTER START/AT IDLE
DESCRIPTION
•  Engine stops unexpectedly at idle, after start, or both.
POSSIBLE CAUSE
•  Engine overheating
•  PCM DTC is stored
•  Erratic signal to PCM
?  APP sensor or related circuit malfunction
?  ECT sensor or related circuit malfunction
?  MAF sensor or related circuit malfunction
?  MAP sensor or related circuit malfunction
?  A/F sensor or related circuit malfunction
?  HO2S or related circuit malfunction
?  Improper air/fuel mixture ratio control
•  Improper operation of A/C system
•  Improper operation of drive-by-wire control system
•  Purge solenoid valve malfunction
•  Open circuit in MAF sensor ground circuit
•  Intermittent open circuit in PCM ground circuit
•  Poor fuel quality
•  Air leakage from intake-air system
•  Vacuum leakage
•  Intake-air system restriction
•  Electrical connector disconnected
•  No battery power supply to PCM or poor ground
•  Fuel leakage
•  No signal from CKP sensor
?  Loose installation
?  Damaged trigger wheel (crankshaft pulley)
?  Open or short circuit in related wiring harness
•  Erratic signal from CMP sensor
?  Loose installation
?  Damaged trigger wheel (intake camshaft)
?  Damaged trigger wheel (exhaust camshaft)
?  Open or short circuit in related wiring harness
•  Inadequate fuel pressure (high or low pressure side)
?  Open or short circuit in the fuel pump (low-side) body or related wiring harness
?  Fuel pressure sensor or related circuit malfunction
?  Fuel pump (low-side) body mechanical malfunction
?  High pressure fuel pump malfunction
?  Spill valve control solenoid valve control circuit malfunction (damage to driver in PCM caused by short circuit to ground system)
?  Spill valve control solenoid valve malfunction (built-into high pressure fuel pump)
?  Relief valve (built-into high pressure fuel pump) malfunction
?  Fuel line restriction
?  Fuel filter clogged (built-into fuel pump unit)
?  Fuel pump unit malfunction
•  Fuel injector malfunction
•  Incorrect fuel injection timing
•  Improper operation of electric variable valve timing control system
?  Electric variable valve timing driver malfunction
?  Electric variable valve timing motor malfunction
?  Electric variable valve timing actuator malfunction
•  Improper operation of hydraulic variable valve timing control system
•  Ignition system malfunction
•  Ignition coil malfunction
•  Low engine compression
•  Improper intake valve timing
•  Improper exhaust valve timing
•  Exhaust system and/or TWC restricted or clogged
•  PCV valve malfunction
•  Injector driver (built-into PCM) malfunction
POSSIBLE CAUSE
Warning
•  The following troubleshooting flow chart contains the fuel system diagnosis and repair procedures. Read the following warnings before performing the fuel system services:
?  Fuel vapor is hazardous. It can easily ignite, causing serious injury and damage. Always keep sparks and flames away from fuel.
?  Highly pressurized fuel may spray out if the fuel line is cut. Due to the following dangers occurring with a fuel spray, always complete the “Fuel Line Safety Procedure” to prevent the fuel from spraying. (See BEFORE SERVICE PRECAUTION [SKYACTIV-G 2.5T].)
•  Fuel may cause irritation if it comes in contact with skin and eyes.
•  If fuel ignites and causes a fire, it may lead to serious injury or death, and damage to property and facilities.
?  Fuel is highly flammable and dangerous. Fuel line spills and leakage can cause serious injury or death, and damage to equipment. Always refer to the “Quick Release Connector Removal/Installation (fuel system)” before performing the fuel hose installation, and execute the “Fuel Leakage Inspection” after installation. (See QUICK RELEASE CONNECTOR REMOVAL/INSTALLATION [SKYACTIV-G 2.5T].) (See AFTER SERVICE PRECAUTION [SKYACTIV-G 2.5T].)
Caution
•  Disconnecting/connecting the quick release connector without cleaning it may possibly cause damage to the fuel pipe and quick release connector. Always clean the 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
VERIFY TIMING OCCURRING MALFUNCTION
•  Verify the symptom.
•  Does the malfunction symptom occur just after the engine is started?
Yes
Perform the symptom troubleshooting “NO.4 HARD TO START/LONG CRANK/ERRATIC START/ERRATIC CRANK”.
(See NO.4 HARD TO START/LONG CRANK/ERRATIC START/ERRATIC CRANK [SKYACTIV-G 2.5T].)
No
Go to the next step.
2
VERIFY IF MALFUNCTION INCLUDES ROUGH IDLING
•  Verify the symptom.
•  Does the engine idle rough?
Yes
Perform the symptom troubleshooting “NO.8 ENGINE RUNS ROUGH/ROLLING IDLE”.
(See NO.8 ENGINE RUNS ROUGH/ROLLING IDLE [SKYACTIV-G 2.5T].)
No
Go to the next step.
3
VERIFY IF MALFUNCTION CAUSE IS OVERHEATING
•  Access the ECT PID using the M-MDS.
•  Is the ECT PID value less than 116 °C {241 °F} during driving?
Yes
Go to the next step.
No
The cause of this concern could be from the cooling system overheating.
•  Perform the symptom troubleshooting “NO.17 COOLING SYSTEM CONCERNS-OVERHEATING”.
4
VERIFY PCM DTC
•  Retrieve PCM DTCs using the M-MDS.
•  Are any DTCs present?
Yes
Go to the applicable DTC inspection.
(See DTC TABLE [PCM (SKYACTIV-G 2.5T)].)
No
Go to the next step.
5
VERIFY CURRENT INPUT SIGNAL STATUS
Caution
•  While performing this step, always operate the vehicle in a safe and lawful manner.
•  When the M-MDS is used to observe monitor system status while driving, be sure to have another technician with you, or record the data in the M-MDS using the PID/DATA MONITOR AND RECORD capturing function and inspect later.
•  Access the following PIDs using the M-MDS:
?  APP1
?  APP2
?  ECT
?  MAF
?  MAP
?  MAP_V
?  O2S11
?  O2S12
?  SHRTFT1
?  LONGFT1
•  Do the PIDs indicate the correct values under the trouble condition?
Yes
Go to the next step.
No
APP1, APP2 PIDs are not as specified:
•  Inspect the APP sensor.
ECT PID is not as specified:
•  Inspect the ECT sensor.
MAF PID is not as specified:
•  Inspect the MAF sensor.
MAP, MAP_V PIDs are not as specified:
•  Inspect the MAP sensor.
O2S11, SHRTFT1, LONGFT1 PIDs are not as specified:
•  Inspect the A/F sensor.
O2S12 PID is not as specified:
•  Inspect the HO2S.
Repair or replace the malfunctioning part according to the inspection results.
•  If the malfunction remains:
?  Perform the “INTERMITTENT CONCERN TROUBLESHOOTING” procedure.
6
INSPECT PCM GROUND CIRCUIT FOR OPEN CIRCUIT
•  Switch the ignition off.
•  Verify that the main relay is removed.
•  Verify that the PCM connector is disconnected.
•  Inspect for continuity between the following harnesses:
?  PCM terminal 2S (wiring harness-side)—Body ground
?  PCM terminal 2T (wiring harness-side)—Body ground
?  PCM terminal 1CK (wiring harness-side)—Body ground
•  Is there continuity?
Yes
Refer to the wiring diagram and verify whether or not there is a common connector between the following terminals:
•  PCM terminal 2S—Body ground
•  PCM terminal 2T—Body ground
•  PCM terminal 1CK—Body ground
If there is a common connector:
•  Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for an open circuit.
•  Repair or replace the malfunctioning part.
If there is no common connector:
•  Inspect for the following:
?  Open circuit between PCM and body ground
?  Loose or lifting ground point
•  Repair or replace the malfunctioning part.
Go to Step 30.
No
Go to the next step.
7
INSPECT PCM POWER SUPPLY CIRCUIT FOR OPEN CIRCUIT
•  Verify that the main relay is removed.
•  Verify that the PCM connector is disconnected.
•  Inspect for continuity between the following terminals (wiring harness-side):
?  Main relay terminal C—PCM terminal 2S
?  Main relay terminal C—PCM terminal 2T
?  Main relay terminal C—PCM terminal 1CK
•  Is there continuity?
Yes
Go to the next step.
No
Refer to the wiring diagram and verify whether or not there is a common connector between the following terminals:
•  Main relay terminal C—PCM terminal 2S
•  Main relay terminal C—PCM terminal 2T
•  Main relay terminal C—PCM terminal 1CK
If there is a common connector:
•  Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for an open circuit.
•  Repair or replace the malfunctioning part.
If there is no common connector:
•  Repair or replace the wiring harness which has an open circuit.
Go to Step 30.
8
INSPECT A/C CUT-OFF CONTROL SYSTEM OPERATION
•  Perform the A/C Cut-off Control System Inspection.
•  Does the A/C cut-off operation work properly?
Yes
Go to the next step.
No
Perform the symptom troubleshooting "NO.23 A/C DOES NOT WORK SUFFICIENTLY" and "NO.24 A/C IS ALWAYS ON OR A/C COMPRESSOR RUNS CONTINUOUSLY".
(See NO.23 A/C DOES NOT WORK SUFFICIENTLY [SKYACTIV-G 2.5T].)
(See NO.24 A/C IS ALWAYS ON OR A/C COMPRESSOR RUNS CONTINUOUSLY [SKYACTIV-G 2.5T].)
9
DETERMINE IF MALFUNCTION CAUSE IS DRIVE-BY-WIRE CONTROL SYSTEM OR OTHER
•  Will the engine run smoothly at part throttle?
Yes
Go to Step 11.
No
Go to the next step.
10
INSPECT DRIVE-BY-WIRE CONTROL SYSTEM OPERATION
•  Perform the Electronic Control Throttle Operation Inspection.
•  Does the drive-by-wire control system work properly?
Yes
Visually inspect the throttle body (damage/scratching).
•  If there is any malfunction:
?  Repair or replace the malfunctioning part according to the inspection results.
•  If there is no malfunction:
?  Go to the next step.
No
Repair or replace the malfunctioning part according to the inspection results.
11
INSPECT PURGE CONTROL SYSTEM OPERATION
•  Perform the Purge Control System Inspection.
•  Does the purge solenoid valve work properly?
Yes
Go to the next step.
No
Repair or replace the malfunctioning part according to the inspection results.
12
INSPECT MAF SENSOR GROUND CIRCUIT FOR OPEN CIRCUIT
•  Measure the voltage at the MAF sensor terminal B.
•  Is the voltage 1.0 V or less?
Yes
Go to the next step.
No
Inspect the MAF sensor ground circuit.
•  If there is any malfunction:
?  Repair or replace the malfunctioning part according to the inspection results.
•  If there is no malfunction:
?  Go to the next step.
13
INSPECT PCM FOR POOR GROUND
•  Verify the PCM ground point condition.
•  Is there any ground point loose or lifting in the PCM?
Yes
Repair the ground point.
No
Go to the next step.
14
INSPECT RELATED PART CONDITION
•  Inspect the following:
?  Fuel quality (proper octane, contamination, winter/summer blend)
?  Intake-air system leakage or restriction
?  Electrical connectors
?  Poor connection for PCM ground and body ground
?  Fuel leakage
?  Vacuum leakage
?  CKP sensor and intake CMP sensor
•  Installation condition
•  Damaged trigger wheel (intake camshaft)
?  Exhaust CMP sensor
•  Installation condition
•  Damaged trigger wheel (exhaust camshaft)
•  Is there any malfunction?
Yes
Service if necessary.
•  Repeat this step.
No
Go to the next step.
15
INSPECT FUEL PRESSURE (HIGH-SIDE)
•  Start the engine and warm it up completely.
•  Access the FUEL_PRES PID using the M-MDS at idle.
•  Is the FUEL_PRES PID value approx. 3 MPa {31 kgf/cm2, 435 psi}?
Yes
Go to Step 19.
No
Lower than 3 MPa {31 kgf/cm2, 435 psi}:
•  Inspect the following:
?  Fuel leakage at the fuel line and fuel injector
?  Fuel pump
•  Perform the Fuel Pump (Low-pressure Side) Operation Inspection.
?  Fuel pressure sensor
?  High pressure fuel pump
•  If there is any malfunction:
?  Repair or replace the malfunctioning part according to the inspection results.
•  If there is no malfunction:
?  Go to Step 18.
Higher than 3 MPa {31 kgf/cm2, 435 psi}:
•  Go to the next step.
16
DETERMINE IF MALFUNCTION CAUSE IS FUEL PRESSURE SENSOR OR HIGH PRESSURE FUEL PUMP
•  Is the vehicle acceleration performance normal?
Yes
Go to the next step.
No
Go to Step 18.
17
INSPECT HIGH FUEL PRESSURE SENSOR
•  Inspect the high fuel pressure sensor.
•  Is there any malfunction?
Yes
Replace the fuel distributor.
(See FUEL INJECTOR REMOVAL/INSTALLATION [SKYACTIV-G 2.5T].)
No
Go to Step 19.
18
INSPECT SPILL VALVE CONTROL SOLENOID VALVE CONTROL CIRCUIT FOR SHORT TO GROUND
•  Switch the ignition off.
•  Disconnect the high pressure fuel pump and PCM connectors.
•  Inspect for continuity between high pressure fuel pump terminal A (wiring harness-side) and body ground.
•  Is there continuity?
Yes
Refer to the wiring diagram and verify whether or not there is a common connector between high pressure fuel pump terminal A and PCM terminal 1EE.
If there is a common connector:
•  Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to ground.
•  Repair or replace the malfunctioning part.
If there is no common connector:
•  Repair or replace the wiring harness which has a short to ground.
If the malfunction remains:
•  Replace the PCM. (damage to driver in PCM)
No
Replace the high pressure fuel pump.
(See HIGH PRESSURE FUEL PUMP REMOVAL/INSTALLATION [SKYACTIV-G 2.5T].)
19
INSPECT FUEL PRESSURE (LOW-SIDE)
•  Connect the fuel pressure gauge between fuel pump and high pressure fuel pump.
•  Measure the low side fuel pressure.
•  Is the low side fuel pressure within specification?
Specification:
•  545—695 kPa {5.56—7.08 kgf/cm2, 79.1—100.0 psi}
Yes
Go to the next step.
No
Inspect the following:
•  Fuel line restriction
•  Fuel filter clogged
?  If there is any malfunction:
•  Repair or replace the malfunctioning part according to the inspection results.
?  If there is no malfunction:
•  Replace the fuel pump unit.
20
INSPECT FUEL INJECTOR OPERATION
•  Perform the Fuel Injector Operation Inspection.
•  Do the fuel injectors operate properly?
Yes
Go to the next step.
No
Repair or replace the malfunctioning part according to the inspection results.
21
INSPECT ENGINE COMPRESSION
•  Measure the compression pressure for each cylinder.
•  Are compression pressures within specification?
Yes
Go to Step 27.
No
Go to the next step.
22
INSPECT ELECTRIC VARIABLE VALVE TIMING DRIVER
•  Inspect the electric variable valve timing driver.
•  Is there any malfunction?
Yes
Replace the electric variable valve timing motor/driver.
(See ELECTRIC VARIABLE VALVE TIMING MOTOR/DRIVER REMOVAL/INSTALLATION [SKYACTIV-G 2.5T].)
No
Go to the next step.
23
INSPECT ELECTRIC VARIABLE VALVE TIMING MOTOR
•  Inspect the electric variable valve timing motor.
•  Is there any malfunction?
Yes
Replace the electric variable valve timing motor/driver.
(See ELECTRIC VARIABLE VALVE TIMING MOTOR/DRIVER REMOVAL/INSTALLATION [SKYACTIV-G 2.5T].)
No
Go to the next step.
24
INSPECT ELECTRIC VARIABLE VALVE TIMING ACTUATOR
•  Inspect the electric variable valve timing actuator.
•  Is there any malfunction?
Yes
Replace the electric variable valve timing actuator.
(See ELECTRIC VARIABLE VALVE TIMING ACTUATOR, HYDRAULIC VARIABLE VALVE TIMING ACTUATOR REMOVAL/INSTALLATION [SKYACTIV-G 2.5T].)
No
Go to the next step.
25
INSPECT HYDRAULIC VARIABLE VALVE TIMING CONTROL SYSTEM OPERATION
•  Perform the Hydraulic Variable Valve Timing Control System Operation Inspection.
•  Is there any malfunction?
Yes
Repair or replace the malfunctioning part according to the inspection results.
No
Go to the next step.
26
INSPECT FOR MALFUNCTION DUE TO DEVIATED VALVE TIMING
•  Inspect the valve timing (timing chain installation condition).
•  Is the valve timing normal?
Yes
Inspect for the following engine internal parts:
•  Cylinder
•  Piston ring
•  Intake valve
•  Exhaust valve
•  Such as cylinder head gasket
?  If there is any malfunction:
•  Repair or replace the malfunctioning part according to the inspection results.
No
Adjust the valve timing to the correct timing.
27
INSPECT IGNITION SYSTEM OPERATION
•  Perform the Spark Test.
•  Is a 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.
28
INSPECT EXHAUST SYSTEM FOR RESTRICTION
•  Inspect for restriction in the exhaust system and the TWC.
•  Is there any restriction?
Yes
Repair or replace the malfunctioning part according to the inspection results.
No
Go to the next step.
29
INSPECT IF MALFUNCTION CAUSE IS PCV VALVE OR INJECTOR DRIVER (PCM INTEGRATED)
•  Inspect the PCV valve.
•  Is there any malfunction?
Yes
Replace the PCV valve.
(See POSITIVE CRANKCASE VENTILATION (PCV) VALVE REMOVAL/INSTALLATION [SKYACTIV-G 2.5T].)
No
Injector driver malfunction.
•  Replace the PCM.
If the problem remains, overhaul the engine.
30
Verify the test results.
•  If normal, return to the diagnostic index to service any additional symptoms.
•  If a malfunction remains, inspect the related Service Information and perform the repair or diagnosis.
?  If the vehicle is repaired, troubleshooting is completed.
?  If the vehicle is not repaired or additional diagnostic information is not available, replace the PCM.