Symptom Chart

SYMPTOM	POSSIBLE CAUSES	ACTION
Engine cranks, but does not fire	Engine breather system disconnected/restricted Engine system fault	Ensure the engine breather system is free from restriction and is correctly installed Using the manufacturer approved diagnostic system, check the engine control module for related DTCs and refer to the relevant DTC index
Engine cranks and fires, but will not start	Purge valve fault Engine system fault	Refer to the relevent service information and check the purge valve Using the manufacturer approved diagnostic system, check the engine control module for related DTCs and refer to the relevant DTC index
Difficult cold start	Engine coolant level/anti-freeze content Battery/charging system fault Engine system fault Purge valve fault	Check the engine coolant level and condition Refer to the relevent service information and check the battery and charging system Using the manufacturer approved diagnostic system, check the engine control module for related DTCs and refer to the relevant DTC index Refer to the relevent service information and check the purge valve
Difficult hot start	Fuel injector leaking Engine system fault Purge valve fault	Check the fuel injectors for leaks Using the manufacturer approved diagnostic system, check the engine control module for related DTCs and refer to the relevant DTC index Refer to the relevent service information and check the purge valve
Difficult to start after hot soak (vehicle standing, engine off, after engine has reached operating temperature)	Fuel injector leaking Engine system fault Purge valve fault	Check the fuel injectors for leaks Using the manufacturer approved diagnostic system, check the engine control module for related DTCs and refer to the relevant DTC index Refer to the relevent service information and check the purge valve
Engine stalls soon after start	Engine breather system disconnected/restricted Engine system fault Intake air system leaking/restricted	Ensure the engine breather system is free from restriction and is correctly installed Using the manufacturer approved diagnostic system, check the engine control module for related DTCs and refer to the relevant DTC index Check the intake air system for leaks and restrictions
Engine hesitates/poor acceleration	Fuel injector leaking Engine system fault Transmission system fault Intake air system leaking/restricted Accelerator pedal travel restricted (carpet, etc)	Check the fuel injectors for leaks Using the manufacturer approved diagnostic system, check the engine control module for related DTCs and refer to the relevant DTC index Using the manufacturer approved diagnostic system, check the transmission control module for related DTCs and refer to the relevant DTC index Check the intake air system for leaks and restrictions Check the accelerator pedal for full travel
Engine backfires	Intake air system leaking/restricted Engine system fault	Check the intake air system for leaks and restrictions Using the manufacturer approved diagnostic system, check the engine control module for related DTCs and refer to the relevant DTC index
Engine surges	Engine system fault	Using the manufacturer approved diagnostic system, check the engine control module for related DTCs and refer to the relevant DTC index
Engine detonates/knocks	Intake air system leaking/restricted Engine system fault	Check the intake air system for leaks and restrictions Using the manufacturer approved diagnostic system, check the engine control module for related DTCs and refer to the relevant DTC index
No throttle response	Engine system fault	Using the manufacturer approved diagnostic system, check the engine control module for related DTCs and refer to the relevant DTC index
Poor throttle response	Engine breather system disconnected/restricted Engine system fault Transmission system fault Intake air system leaking/restricted	Ensure the engine breather system is free from restriction and is correctly installed Using the manufacturer approved diagnostic system, check the engine control module for related DTCs and refer to the relevant DTC index Using the manufacturer approved diagnostic system, check the transmission control module for related DTCs and refer to the relevant DTC index Check the intake air system for leaks and restrictions