Inspection and verification
1. Check the validity of the customer's complaint.
2. Visually inspect for obvious mechanical and electrical problems.
Mechanical factors | Electrical Factors |
3. If there is an obvious cause for the problem you identified or the customer described, fix it before proceeding with the next steps (if possible).
4. Using an approved diagnostic system or a suitable scan tool, read all DTCs (DTC), before going to the Symptoms Table or DTC Index.
Clear all DTCs after troubleshooting.
Symptom table
sign (general) | sign (characteristic) | Possible reasons | Action |
Lack of launch | Engine crankshaft does not turn | Make sure the security system is disabled. Check the operation of the ECM relay. Check the condition and charge of the battery. For starting system checks, refer to the appropriate section in the workshop manual. Check if the engine turns by hand. | |
Lack of launch | The engine crankshaft rotates, but flashes do not occur | Check the level and condition of the fuel. For ignition and fuel system checks, refer to the appropriate section in the workshop manual. Refer to the guided diagnostic routine on the approved diagnostic system for CKP sensor and wiring harness checks. If an ECM malfunction is suspected, refer to the warranty policy and procedures manual. | |
Lack of launch | The crankshaft of the engine scrolls, there are flashes, but the engine does not start | For purge valve, fuel system, and ignition system checks, refer to the appropriate section in the workshop manual. | |
Difficult start | Cold start difficulties | Check the condition of the coolant. Check the condition and charge of the battery. For CKP sensor checks, refer to the guided diagnostic program on the approved diagnostic system. For fuel system and purge valve checks, refer to the appropriate section in the workshop manual. | |
Difficult start | Hot Start Difficulties | For injector and fuel system checks, fuel temperature sensor, IAT sensor, and MAF sensor, refer to the guided diagnostic program on the approved diagnostic system. For purge valve and ignition system checks, refer to the appropriate section in the workshop manual. | |
Difficult start | Difficulty starting after a hot soak (the vehicle remains stationary for a while after the engine has reached operating temperature) | For injector and fuel system checks, fuel temperature sensor, IAT sensor, and MAF sensor, refer to the guided diagnostic program on the approved diagnostic system. For purge valve and ignition system checks, refer to the appropriate section in the workshop manual. | |
Difficult start | Engine crankshaft turns too fast/slow | Check compression. Check the condition and charge of the battery. For starting system checks, refer to the appropriate section in the workshop manual. | |
Engine stalls | Engine stalls shortly after starting | Check engine ventilation system. Check the operation of the ECM relay. For MAF sensor checks, refer to the guided diagnostic program on the approved diagnostic system. Ignition system checks are described in the appropriate section of the workshop manual. For information on the air intake system and fuel lines, refer to the appropriate section in the workshop manual. For FRP sensor checks, refer to the guided diagnostic program on the approved diagnostic system. | |
Engine stalls | Engine stalls when braking | Check the operation of the ECM relay. For throttle position sensor checks, refer to the guided diagnostic program on the approved diagnostic system. | |
Engine stalls | Engine stalls at steady speed | Check the operation of the ECM relay. For CKP sensor and TP sensor checks, refer to the guided diagnostic program on the approved diagnostic system. | |
Engine stalls | Engine stalls when cruise control is on | ECM relay | Check the operation of the ECM relay. |
Engine stalls | Engine stalls when maneuvering | Check the operation of the ECM relay. For throttle position sensor checks, refer to the guided diagnostic program on the approved diagnostic system. For information on the accessory drive and gearbox, refer to the appropriate section in the workshop manual. Check for CAN DTCs. | |
Poor handling | Engine stalling on acceleration/poor acceleration | For information on checking the fuel pump, fuel lines and air intake system, refer to the appropriate section in the workshop manual. For throttle position sensor and throttle motor checks, refer to the guided diagnostic program on the approved diagnostic system. Ignition system checks are described in the appropriate section of the workshop manual. Check for DTCs for HO2 sensors, refer to the DTC Index. For gearbox information, refer to the appropriate section in the workshop manual. Check the movement of the accelerator pedal. For throttle position sensor checks, refer to the guided diagnostic program on the approved diagnostic system. | |
Poor handling | Backfires in the engine | For information about the fuel pump, fuel lines and air intake system, refer to the appropriate section in the workshop manual. For MAF sensor checks, refer to the guided diagnostic program on the approved diagnostic system. Check for DTCs for HO2 sensors, refer to the DTC Index. Ignition system checks are described in the appropriate section of the workshop manual. For throttle position sensor checks, refer to the guided diagnostic program on the approved diagnostic system. | |
Poor handling | Engine Jerks | For information about the fuel pump and fuel lines, refer to the appropriate section in the workshop manual. For MAF sensor, throttle position sensor, and throttle motor checks, refer to the guided diagnostic program on the approved diagnostic system. Ignition system checks are described in the appropriate section of the workshop manual. | |
Poor handling | Detonation / knocking in the engine | Refer to the guided diagnostic program on the approved diagnostic system for the knock sensor circuit tests. For information about the fuel pump and fuel lines, refer to the appropriate section in the workshop manual. For FRP sensor and MAF sensor checks, refer to the guided diagnostic program on the approved diagnostic system. Check for DTCs for HO2 sensors, refer to the DTC Index. For information about the air intake system, refer to the appropriate section in the workshop manual. If an ECM malfunction is suspected, refer to the warranty policy and procedures manual. | |
Poor handling | Lack of throttle response | For throttle position sensor and throttle motor checks, refer to the guided diagnostic program on the approved diagnostic system. | |
Poor handling | Disabling or disabling the cruise control system | Check the message center for a default message. For cruise control system switches, refer to the appropriate section in the workshop manual. For throttle position sensor checks, refer to the guided diagnostic program on the approved diagnostic system. Check for CAN DTCs. | |
Poor handling | Poor throttle response | For throttle position sensor, eCt sensor, and MAF sensor checks, refer to the guided diagnostic program on the approved diagnostic system. For information about the transmission, air intake system and ventilation system, refer to the appropriate section in the workshop manual. | |
Poor handling | The engine management system has moved to default values, warning lamp and messages. Please refer to the instruction manual. | For throttle position sensor, MAF sensor, and ECT sensor checks, refer to the guided diagnostic program on the approved diagnostic system. |
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