Diagnostic Procedure

WARNING: This page is about a different variant/trim than selected.

ENGINE STALLS/QUITS, ENGINE RUNS ROUGH, MISSES, BUCK/JERK, HESITATION/STUMBLE, SURGES (VIN Y) DIAGNOSTIC PROCEDURE

Step	Inspection	Results	Action
1	VERIFY IF MALFUNCTION INCLUDES HARD ENGINE STARTING Is the engine unable to start after it has stalled? NOTE: If the ignition is not switched off or ACC after the engine stalls, and then an engine restart is attempted, the PCM corrects the difference between CKP sensor and CMP sensor signals caused by engine stalling, which may result in more time needed to restart the engine.	Yes	If the engine is unable to start, perform the symptom troubleshooting [WILL NOT CRANK] and [CRANKS NORMALLY BUT WILL NOT START]. (See WILL NOT CRANK (VIN Y) .) (See CRANKS NORMALLY BUT WILL NOT START (VIN Y) .)
1		No	Go to the next step.
2	VERIFY IF MALFUNCTION INCLUDES ROUGH IDLING Does the engine idle rough?	Yes	Perform the symptom troubleshooting [ENGINE RUNS ROUGH/ROLLING IDLE]. (See ENGINE RUNS ROUGH/ROLLING IDLE (VIN Y) .)
2		No	Go to the next step.
3	DETERMINE IF MALFUNCTION CAUSE IS OVERHEATING OR OTHER WARNING: Observe legal speed limits when driving the vehicle and perform the procedure in a location where safety can be assured. To prevent an accident, work with two people when the vehicle is being driven (one person drives vehicle, other person operates M-MDS). Access the PCM PID [ECT] using the M-MDS. Is the PID value less than 116°C {241°F} during driving?	Yes	Go to the next step.
3		No	The cause of this concern could be from the cooling system overheating. Perform the symptom troubleshooting [COOLING SYSTEM CONCERNS OVERHEATING]. (See COOLING SYSTEM CONCERNS-OVERHEATING (VIN Y) .)
4	CONFIRM DRIVE-BY-WIRE CONTROL SYSTEM OPERATES WITH BRAKE OVERRIDE SYSTEM Perform the DTC inspection for the PCM. (See DTC INSPECTION .) Is the DTC P2299:00 present?	Yes	Repair the malfunctioning location according to the applicable DTC troubleshooting. (Drive-by-wire control system operates with brake override system.) (See P2299:00 [PCM (VIN Y)] .)
4		No	Go to the next step.
5	VERIFY PCM DTCs Perform the DTC inspection for the PCM. (See DTC INSPECTION .) Are any DTCs displayed?	Yes	Repair or replace the malfunctioning location according to the applicable DTC troubleshooting. (See DTC TABLE [PCM (VIN Y)] .)
5		No	Go to the next step.
6	VERIFY CURRENT INPUT SIGNAL STATUS WARNING: Observe legal speed limits when driving the vehicle and perform the procedure in a location where safety can be assured. To prevent an accident, work with two people when the vehicle is being driven (one person drives vehicle, other person operates M-MDS). Access the following PIDs using the M-MDS: PCM: APP1 APP2 ECT ECT_VOLT FUEL_PRES IAT MAF MAP MAP_VOLT A/F_SEN_CUR HO2S_OUT_VOLT SHRT_FUEL_TRIM LONG_FUEL_TRIM Do the PIDs indicate the correct values under the malfunction condition? (See PID/DATA MONITOR TABLE [PCM (VIN Y)] .)	Yes	Go to the next step.
6		No	APP1, APP2 PIDs are not as specified: Inspect the APP sensor No. 1 and No. 2. (Refer to ACCELERATOR PEDAL POSITION (APP) SENSOR INSPECTION (VIN Y) .) ECT, ECT_VOLT PIDs are not as specified: Inspect the ECT sensor. (Refer to ENGINE COOLANT TEMPERATURE (ECT) SENSOR INSPECTION (VIN Y) .) FUEL_PRES PID is not as specified: Inspect the high fuel pressure sensor. (Refer to HIGH FUEL PRESSURE SENSOR INSPECTION (VIN Y) .) IAT PID is not as specified: Inspect the IAT sensor No. 1. (Refer to INTAKE AIR TEMPERATURE (IAT) SENSOR INSPECTION (VIN Y) .) MAF PID is not as specified: Inspect the MAF sensor. (Refer to MASS AIR FLOW (MAF) SENSOR INSPECTION (VIN Y) .) MAP, MAP_VOLT PIDs are not as specified: Inspect the MAP sensor. (Refer to MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR INSPECTION (VIN Y) .) A/F_SEN_CUR, SHRT_FUEL_TRIM, LONG_FUEL_TRIM PIDs are not as specified: Inspect the A/F sensor. (Refer to AIR FUEL RATIO (A/F) SENSOR INSPECTION (VIN Y) .) HO2S_OUT_VOLT PID is not as specified: Inspect the HO2S. (Refer to HEATED OXYGEN SENSOR (HO2S) INSPECTION (VIN Y) .) Repair or replace the malfunctioning location. If the malfunction remains: Inspect communication error between TCM and PCM. Repair or replace the malfunctioning location and perform the repair completion verification 1. Perform the [Action for Non-repeatable Malfunction] procedure. (See TROUBLESHOOTING PROCEDURE .)
7	VERIFY A/C SYSTEM FOR MALFUNCTION Verify the operation of the A/C system. Is the A/C system operation normal?	Yes	Go to the next step.
7		No	Perform the symptom troubleshooting [A/C OPERATION MALFUNCTION] and [A/C ON CONSTANTLY, OR A/C COMPRESSOR CONTINUES TO OPERATE].
8	DETERMINE IF MALFUNCTION CAUSE IS DRIVE-BY-WIRE CONTROL SYSTEM OR OTHER Will the engine run smoothly at part throttle?	Yes	Go to Step 10.
8		No	Go to the next step.
9	INSPECT DRIVE-BY-WIRE CONTROL SYSTEM OPERATION Perform the Electronic Control Throttle Operation Inspection. (See ENGINE CONTROL SYSTEM OPERATION INSPECTION (VIN Y) .) 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 location and perform the repair completion verification 1. If there is no malfunction: Go to the next step.
9		No	Repair or replace the malfunctioning location and perform the repair completion verification 1.
10	INSPECT FUEL INJECTOR OPERATION Perform the Fuel Injector Operation Inspection. (Refer to FUEL INJECTOR INSPECTION (VIN Y) .) Do the fuel injectors operate properly?	Yes	Go to the next step.
10		No	Repair or replace the malfunctioning location and perform the repair completion verification 1.
11	INSPECT PURGE CONTROL SYSTEM OPERATION Perform the Purge Control System Inspection. (Refer to PURGE SOLENOID VALVE INSPECTION (VIN Y) .) Does the purge solenoid valve work properly?	Yes	Go to the next step.
11		No	Repair or replace the malfunctioning location and perform the repair completion verification 1.
12	INSPECT CURRENT A/F SENSOR SIGNAL Inspect the A/F sensor. (Refer to AIR FUEL RATIO (A/F) SENSOR INSPECTION (VIN Y) .) Is there any malfunction?	Yes	Go to the next step.
12		No	Go to Step 14.
13	DETERMINE IF MALFUNCTION CAUSE IS A/F SENSOR MALFUNCTION OR A/F SENSOR RELATED WIRING HARNESS MALFUNCTION NOTE: If the inspection in Step 13 is performed, the PCM detects a DTC and performs fail-safe control. After performing the inspection, clear DTCs using the M-MDS. Switch the ignition off. Disconnect the A/F sensor connector. (Refer to AIR FUEL RATIO (A/F) SENSOR REMOVAL/INSTALLATION (VIN Y) .) Verify the symptom. Has the malfunction symptom been eliminated?	Yes	Replace the A/F sensor and perform the repair completion verification 1. (Refer to AIR FUEL RATIO (A/F) SENSOR REMOVAL/INSTALLATION (VIN Y) .)
13		No	Inspect the following: Exhaust system leakage between exhaust manifold and A/F sensor Loose installation of A/F sensor If there is any malfunction: Repair or replace the malfunctioning location and perform the repair completion verification 1. If there is no malfunction: Inspect the A/F sensor signal circuit. Repair or replace the suspected wiring harness if necessary and perform the repair completion verification 1
14	INSPECT RELATED PART CONDITION Inspect the following: Poor fuel quality (proper octane, contamination, winter/summer blend) Air leakage from intake-air system Vacuum leakage Intake-air system restriction Air cleaner element Fuel leakage in fuel system Engine mount installation loose CKP sensor and intake CMP sensor Installation condition (Refer to CRANKSHAFT POSITION (CKP) SENSOR REMOVAL/INSTALLATION (VIN Y) .) (Refer to CAMSHAFT POSITION (CMP) SENSOR REMOVAL/INSTALLATION (VIN Y) .) Damaged trigger wheel (intake camshaft) Exhaust CMP sensor Installation condition (Refer to CAMSHAFT POSITION (CMP) SENSOR REMOVAL/INSTALLATION (VIN Y) .) Damaged trigger wheel (exhaust camshaft) Is there any malfunction?	Yes	Repair or replace the malfunctioning location and perform the repair completion verification 1.
14		No	Go to the next step.
15	INSPECT FUEL PRESSURE (HIGH-SIDE) Start the engine and warm it up completely. Access the PCM PID [FUEL_PRES] using the M-MDS at idle. Is the PID value within specification? Specification: Approx. 10 MPa {102 kgf/cm ² , 1450 psi}	Yes	Go to Step 17.
15		No	Lower than specification: Inspect the following: Fuel leakage at the fuel line and fuel injector Fuel pump Perform the Fuel Pump (Low-pressure side) Operation Inspection. (Refer to FUEL PUMP OPERATION INSPECTION .) High fuel pressure sensor (Refer to HIGH FUEL PRESSURE SENSOR INSPECTION (VIN Y) .) High pressure fuel pump (Refer to HIGH PRESSURE FUEL PUMP INSPECTION (VIN Y) .) If there is any malfunction: Repair or replace the malfunctioning location and perform the repair completion verification 1. If there is no malfunction: Go to the next step. Higher than specification: Go to the next step.
16	INSPECT WIRING HARNESS (INCLUDING CONNECTOR/TERMINAL) BETWEEN PCM AND SPILL VALVE CONTROL SOLENOID VALVE (HIGH PRESSURE FUEL PUMP) FOR MALFUNCTION Inspect the applicable circuit. (see CIRCUIT INSPECTION .) (see CONNECTOR INSPECTION .) Is the circuit normal?	Yes	Replace the high pressure fuel pump and perform the repair completion verification 1. (Refer to HIGH PRESSURE FUEL PUMP INSPECTION (VIN Y) .)
16		No	Repair or replace the malfunctioning location and perform the repair completion verification 1.
17	INSPECT FUEL PRESSURE (LOW-SIDE) Connect the fuel pressure gauge between fuel pump and high pressure fuel pump. Measure the low side fuel pressure. (Refer to FUEL LINE PRESSURE INSPECTION (VIN Y) .) Is the low side fuel pressure within specification? Specification: 475-555 kPa {4.85-5.65 kgf/cm ² , 68.9-80.4 psi}	Yes	Go to the next step.
17		No	Inspect the following: Fuel line restriction Fuel filter clogged If there is any malfunction: Repair or replace the malfunctioning location and perform the repair completion verification 1. If there is no malfunction: Replace the fuel pump unit and perform the repair completion verification 1. (Refer to FUEL PUMP UNIT REMOVAL/INSTALLATION (VIN Y) .)
18	INSPECT THROTTLE BODY FOR CLOGGING Visually inspect the throttle valve. (Refer to THROTTLE BODY INSPECTION (VIN Y) .) Is the throttle body normal?	Yes	Clean the throttle valve and perform the repair completion verification 1.
18		No	Go to the next step.
19	INSPECT ENGINE COMPRESSION Measure the compression pressure for each cylinder. (Refer to COMPRESSION INSPECTION (VIN Y) .) Are compression pressures within specification?	Yes	Go to Step 25.
19		No	Go to the next step.
20	VERIFY ELECTRIC VARIABLE VALVE TIMING DRIVER FOR MALFUNCTION Inspect the applicable part. (Refer to ELECTRIC VARIABLE VALVE TIMING MOTOR/DRIVER INSPECTION (VIN Y) .) Is the part normal?	Yes	Go to the next step.
20		No	Repair or replace the malfunctioning location and perform the repair completion verification 1. (Refer to ELECTRIC VARIABLE VALVE TIMING MOTOR/DRIVER REMOVAL/INSTALLATION (VIN Y) .)
21	VERIFY ELECTRIC VARIABLE VALVE TIMING MOTOR FOR MALFUNCTION Inspect the applicable part. (Refer to ELECTRIC VARIABLE VALVE TIMING MOTOR/DRIVER INSPECTION (VIN Y) .) Is the part normal?	Yes	Go to the next step.
21		No	Repair or replace the malfunctioning location and perform the repair completion verification 1. (Refer to ELECTRIC VARIABLE VALVE TIMING MOTOR/DRIVER REMOVAL/INSTALLATION (VIN Y) .)
22	VERIFY ELECTRIC VARIABLE VALVE TIMING ACTUATOR FOR MALFUNCTION Inspect the applicable part. (Refer to ELECTRIC VARIABLE VALVE TIMING ACTUATOR INSPECTION (VIN Y) .) Is the part normal?	Yes	Go to the next step.
22		No	Repair or replace the malfunctioning location and perform the repair completion verification 1. (Refer to ELECTRIC VARIABLE VALVE TIMING ACTUATOR, HYDRAULIC VARIABLE VALVE TIMING ACTUATOR REMOVAL/INSTALLATION (VIN Y) .)
23	INSPECT HYDRAULIC VARIABLE VALVE TIMING CONTROL SYSTEM OPERATION Perform the Hydraulic Variable Valve Timing Control System Operation Inspection. (Refer to OIL CONTROL VALVE (OCV) INSPECTION (VIN Y) .) Is there any malfunction?	Yes	Repair or replace the malfunctioning location and perform the repair completion verification 1.
23		No	Go to the next step.
24	INSPECT FOR MALFUNCTION DUE TO DEVIATED VALVE TIMING Inspect the valve timing (timing chain installation condition). (Refer to TIMING CHAIN REMOVAL/INSTALLATION (VIN Y) .) 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 location and perform the repair completion verification 1.
24		No	Adjust the valve timing to the correct timing and perform the repair completion verification 1.
25	INSPECT IGNITION SYSTEM OPERATION Perform the Spark Test. (Refer to SPARK INSPECTION (VIN Y) .) Is a strong blue spark visible at each cylinder?	Yes	Go to the next step.
25		No	Repair or replace the malfunctioning location and perform the repair completion verification 1.
26	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 location and perform the repair completion verification 1.
26		No	Go to the next step.
27	VERIFY PCV VALVE FOR MALFUNCTION Inspect the applicable part. (Refer to POSITIVE CRANKCASE VENTILATION (PCV) VALVE INSPECTION (VIN Y) .) Is the part normal?	Yes	Go to the next step.
27		No	Repair or replace the malfunctioning location and perform the repair completion verification 1. (Refer to POSITIVE CRANKCASE VENTILATION (PCV) VALVE REMOVAL/INSTALLATION (VIN Y) .)
28	INSPECT IF MALFUNCTION CAUSE IS CHECK VALVE OR INJECTOR DRIVER (PCM INTEGRATED) Inspect the check valve. (Refer to applicable CHECK VALVE INSPECTION (VIN Y) .) Is there any malfunction?	Yes	Replace the check valve and perform the repair completion verification 1. (Refer to CHECK VALVE (EMISSION SYSTEM) REMOVAL/INSTALLATION (VIN Y) .)
28		No	Injector driver malfunction. Replace the PCM. (Refer to PCM REMOVAL/INSTALLATION (VIN Y) .) If the problem remains, overhaul the engine and perform the repair completion verification 1.
Repair completion verification 1	VERIFY THAT VEHICLE IS REPAIRED Install/connect the part removed/disconnected during the troubleshooting procedure. Has the malfunction symptom been eliminated?	Yes	Complete the symptom troubleshooting. (Explain contents of repair to customer)
Repair completion verification 1		No	Refer to the controller area network (CAN) malfunction diagnosis flow to inspect for a CAN communication error. (See MALFUNCTION DIAGNOSIS FLOW [CONTROLLER AREA NETWORK (CAN)] .) If the CAN communication is normal, perform the diagnosis from Step 1. If the malfunction recurs, replace the PCM. (Refer to PCM REMOVAL/INSTALLATION (VIN Y) .)