Diagnostic Procedure

ENGINE NOISE (SKYACTIV-G, US) DIAGNOSTIC PROCEDURE

Step	Inspection	Results	Action
1	VERIFY SYMPTOM Verify the occurring sound.	-	Buzzing sound is heard from exhaust pipe during cold engine start: Go to the next step. Squeal, click, or chirp sound is heard: Go to Step 3. Thumping/rattling or creaking sound is heard: Go to Step 4. Hissing sound is heard: Go to Step 5. Clattering sound is heard: Go to Step 6. Pulsing sound is heard: (VIN M) Go to Step 7. Lightly tapping or rumbling sound is heard: Go to Step 8. Other noise is heard: Go to Step 9.
2	BUZZING SOUND IS HEARD FROM EXHAUST PIPE DURING COLD ENGINE START Verify the sound from the exhaust pipe during a cold engine start. Does the sound disappear after approx. 30 s have elapsed?	Yes	NOTE: During a cold engine start, sound occurs for up to approx. 30 s with fast idle up for a drive-by-wire control and the warm-up promotion spark retard correction for ignition timing control. Perform the repair completion verification because the operation is normal.
2		No	Inspect the following: Exhaust system installation condition Intake system installation condition If there is any malfunction: Repair or replace the malfunctioning location and perform the repair completion verification. If there is no malfunction: Go to repair completion verification.
3	VERIFY IF THERE IS SQUEAL, CLICK, OR CHIRP SOUND Inspect the following: Engine oil level Solenoid valves installation Drive belt tension Generator installation Auto tensioner bearing damaged Splash shield or under cover loose Is there any malfunction?	Yes	Repair or replace the malfunctioning location and perform the repair completion verification.
3		No	Go to repair completion verification.
4	VERIFY IF THERE IS THUMPING/RATTLING OR CREAKING SOUND Inspect the following: Drive belt tension Loose parts in engine compartment Loose fitting heater hoses vibrating the heater hose bracket protector Is there any malfunction?	Yes	Repair or replace the malfunctioning location and perform the repair completion verification.
4		No	Go to repair completion verification.
5	VERIFY IF THERE IS HISSING SOUND Inspect the following: Vacuum leakage Spark plug loose Intake-air system leakage Is there any malfunction?	Yes	Repair or replace the malfunctioning location and perform the repair completion verification.
5		No	Go to repair completion verification.
6	VERIFY IF THERE IS CLATTERING SOUND Inspect the location of rattle for loose parts. Is there any malfunction?	Yes	Repair or replace the malfunctioning location and perform the repair completion verification.
6		No	Go to repair completion verification.
7	VERIFY IF THERE IS PULSING SOUND Inspect the exhaust shutter valve. (See EXHAUST SHUTTER VALVE INSPECTION [SKYACTIV-G (VIN M (US))] .) Is there any malfunction?	Yes	Repair or replace the malfunctioning location and perform the repair completion verification.
7		No	Go to repair completion verification.
8	VERIFY IF THERE IS LIGHTLY TAPPING OR RUMBLING SOUND Inspect the following: Exhaust system installation condition Intake system installation condition Is there any malfunction?	Yes	Repair or replace the malfunctioning location and perform the repair completion verification.
8		No	Go to repair completion verification.
9	VERIFY IF THERE IS KNOCK SOUND Is knocking noise present?	Yes	Perform the symptom troubleshooting "KNOCKING/PINGING-ACCELERATION/CRUISE". (See KNOCKING/PINGING-ACCELERATION/CRUISE (US) .)
9	VERIFY IF THERE IS KNOCK SOUND Is knocking noise present?	No	If noise comes from engine internal: Inspect the following: Timing chain Tappet noise Hydraulic lash adjuster (HLA) noise Electric variable valve timing actuator Hydraulic variable valve timing actuator Engine compression Repair or replace the malfunctioning location and perform the repair completion verification.
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 CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW [(US)] .) If the CAN communication is normal, perform the diagnosis from Step 1. If the malfunction recurs, go to the next step.
Repair completion verification 2	VERIFY IF MALFUNCTION IS CAUSED BY NOT PERFORMING PCM REPROGRAMMING Verify repair information and verify that there is a new calibration in the PCM. Is there a new calibration in the PCM?	Yes	Perform the PCM reprogramming and verify if the malfunction symptom was corrected. If the malfunction recurs, replace the PCM. (See PCM REMOVAL/INSTALLATION [SKYACTIV-G (VIN M (US))] .) (See PCM REMOVAL/INSTALLATION [SKYACTIV-G (VIN L (US))] .)
Repair completion verification 2		No	Replace the PCM. (See PCM REMOVAL/INSTALLATION [SKYACTIV-G (VIN M (US))] .) (See PCM REMOVAL/INSTALLATION [SKYACTIV-G (VIN L (US))] .)