NO.21 ENGINE NOISE [WITHOUT CYLINDER DEACTIVATION (SKYACTIV-G 2.0, SKYACTIV-G 2.5)]

21	ENGINE NOISE
DESCRIPTION	• Engine noise from under bonnet.
POSSIBLE CAUSE	Buzzing sound is heard from exhaust pipe during cold engine start: 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. • Sound occurs from drive-by-wire control, ignition control (vehicle is normal) • Dynamic damper loose • Exhaust system installation condition • Intake system installation condition Squeal, click, or chirp noise: • Improper engine oil level • Loose installation of solenoid valves • Improper drive belt tension • Generator installation • Auto tensioner bearing malfunction • Splash shield or under cover loose (splash water to drive belt) Thumping / rattling or creaking sound noise: • Improper drive belt tension • Loose parts • Loose fitting heater hoses vibrating the heater hose bracket protector Hissing sound noise: • Vacuum leakage • Loose spark plug • Air leakage from the intake-air system Clattering noise: • Loose parts Lightly tapping or rumbling noise: • Dynamic damper loose • Exhaust system loose • Intake-air system loose Other noise: • Electric variable valve timing actuator malfunction • Hydraulic variable valve timing actuator malfunction • Timing chain noise • Hydraulic lash adjuster (HLA) noise 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 [WITHOUT CYLINDER DEACTIVATION (SKYACTIV-G 2.0, SKYACTIV-G 2.5)].) • 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 (FUEL SYSTEM) REMOVAL/INSTALLATION [WITHOUT CYLINDER DEACTIVATION (SKYACTIV-G 2.0, SKYACTIV-G 2.5)].) (See AFTER SERVICE PRECAUTION [WITHOUT CYLINDER DEACTIVATION (SKYACTIV-G 2.0, SKYACTIV-G 2.5)].) 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.

ENGINE NOISE

DESCRIPTION

• Engine noise from under bonnet.

POSSIBLE CAUSE

Buzzing sound is heard from exhaust pipe during cold engine start:

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.

• Sound occurs from drive-by-wire control, ignition control (vehicle is normal)

• Dynamic damper loose

• Exhaust system installation condition

• Intake system installation condition

Squeal, click, or chirp noise:

• Improper engine oil level

• Loose installation of solenoid valves

• Improper drive belt tension

• Generator installation

• Auto tensioner bearing malfunction

• Splash shield or under cover loose (splash water to drive belt)

Thumping / rattling or creaking sound noise:

• Improper drive belt tension

• Loose parts

• Loose fitting heater hoses vibrating the heater hose bracket protector

Hissing sound noise:

• Vacuum leakage

• Loose spark plug

• Air leakage from the intake-air system

Clattering noise:

• Loose parts

Lightly tapping or rumbling noise:

• Dynamic damper loose

• Exhaust system loose

• Intake-air system loose

Other noise:

• Electric variable valve timing actuator malfunction

• Hydraulic variable valve timing actuator malfunction

• Timing chain noise

• Hydraulic lash adjuster (HLA) noise

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 [WITHOUT CYLINDER DEACTIVATION (SKYACTIV-G 2.0, SKYACTIV-G 2.5)].)

• 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 (FUEL SYSTEM) REMOVAL/INSTALLATION [WITHOUT CYLINDER DEACTIVATION (SKYACTIV-G 2.0, SKYACTIV-G 2.5)].) (See AFTER SERVICE PRECAUTION [WITHOUT CYLINDER DEACTIVATION (SKYACTIV-G 2.0, SKYACTIV-G 2.5)].)

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.

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. Lightly tapping or rumbling sound is heard: • Go to Step 7. Other noise is heard: • Go to Step 8.
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. Go to Step 9 because the operation is normal.
No	Inspect the following: • Exhaust system installation condition • Intake system installation condition ― If there is any malfunction: • Repair or replace the malfunctioning part according to the inspection results. ― If there is no malfunction: • Go to Step 9.
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 part according to the inspection results.
No	Go to Step 9.
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 part according to the inspection results.
No	Go to Step 9.
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 part according to the inspection results.
No	Go to Step 9.
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 part according to the inspection results.
No	Go to Step 9.
7	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 part according to the inspection results.
No	Go to Step 9.
8	VERIFY IF THERE IS KNOCK SOUND • Is knocking noise present?	Yes	Perform the symptom troubleshooting “NO.13 KNOCKING/PINGING-ACCELERATION/CRUISE”. (See NO.13 KNOCKING/PINGING-ACCELERATION/CRUISE [WITHOUT CYLINDER DEACTIVATION (SKYACTIV-G 2.0, SKYACTIV-G 2.5)].)
No	If noise comes from engine internal: • Inspect the following: ― Timing chain ― Hydraulic lash adjuster (HLA) noise ― Electric variable valve timing actuator ― Hydraulic variable valve timing actuator ― Engine compression • Repair or replace the malfunctioning part according to the inspection results.
9	Verify the test results. • If normal, return to the diagnostic index to service any additional symptoms. (See SYMPTOM DIAGNOSTIC INDEX [WITHOUT CYLINDER DEACTIVATION (SKYACTIV-G 2.0, SKYACTIV-G 2.5)].) • 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. (See PCM REMOVAL/INSTALLATION [WITHOUT CYLINDER DEACTIVATION (SKYACTIV-G 2.0, SKYACTIV-G 2.5)].)

STEP

INSPECTION

RESULTS

ACTION

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.

Lightly tapping or rumbling sound is heard:

• Go to Step 7.

Other noise is heard:

• Go to Step 8.

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.

Go to Step 9 because the operation is normal.

Inspect the following:

• Exhaust system installation condition

• Intake system installation condition

― If there is any malfunction:

• Repair or replace the malfunctioning part according to the inspection results.

― If there is no malfunction:

• Go to Step 9.

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 part according to the inspection results.

Go to Step 9.

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 part according to the inspection results.

Go to Step 9.

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 part according to the inspection results.

Go to Step 9.

VERIFY IF THERE IS CLATTERING SOUND

• Inspect the location of rattle for loose parts.

• Is there any malfunction?

Yes

Repair or replace the malfunctioning part according to the inspection results.

Go to Step 9.

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 part according to the inspection results.

Go to Step 9.

VERIFY IF THERE IS KNOCK SOUND

• Is knocking noise present?

Yes

Perform the symptom troubleshooting “NO.13 KNOCKING/PINGING-ACCELERATION/CRUISE”.

(See NO.13 KNOCKING/PINGING-ACCELERATION/CRUISE [WITHOUT CYLINDER DEACTIVATION (SKYACTIV-G 2.0, SKYACTIV-G 2.5)].)

If noise comes from engine internal:

• Inspect the following:

― Timing chain

― Hydraulic lash adjuster (HLA) noise

― Electric variable valve timing actuator

― Hydraulic variable valve timing actuator

― Engine compression

• Repair or replace the malfunctioning part according to the inspection results.

Verify the test results.

• If normal, return to the diagnostic index to service any additional symptoms.

(See SYMPTOM DIAGNOSTIC INDEX [WITHOUT CYLINDER DEACTIVATION (SKYACTIV-G 2.0, SKYACTIV-G 2.5)].)

• 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.

(See PCM REMOVAL/INSTALLATION [WITHOUT CYLINDER DEACTIVATION (SKYACTIV-G 2.0, SKYACTIV-G 2.5)].)