NO.21 ENGINE NOISE [SKYACTIV-G 2.0, SKYACTIV-G 2.5]

id0103g3802700

21

ENGINE NOISE
DESCRIPTION
•  Engine noise from under bonnet.
POSSIBLE CAUSE
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 /rumble or grinding sound noise:
•  Improper drive belt tension
•  Loose parts
•  Loose fitting heater hoses vibrating the heater hose bracket protector
Hiss sound noise:
•  Vacuum leakage
•  Loose spark plug
•  Air leakage from the intake-air system
Rattle noise:
•  Loose parts
Rap or roar 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.
•  Fuel line spills and leakage are dangerous. Fuel can ignite and cause serious injury or death and damage. Fuel can also irritate skin and eyes. To prevent this, always complete “BEFORE SERVICE PRECAUTION” and “AFTER SERVICE PRECAUTION” described in this manual. (See BEFORE SERVICE PRECAUTION [SKYACTIV-G 2.0, SKYACTIV-G 2.5].) (See AFTER SERVICE PRECAUTION [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 matter.

Diagnostic Procedure

STEP

INSPECTION

RESULTS

ACTION
1
VERIFY IF THERE IS SQUEAL, CLICK, OR CHIRP SOUND
•  Is squeal, click or chirp sound present?
Yes
Inspect the following:
•  Engine oil level
•  Solenoid valves installation
•  Drive belt tension
•  Generator installation
•  Auto tensioner bearing damaged
•  Splash shield or under cover loose
―  If there is any malfunction:
•  Repair or replace the malfunctioning part according to the inspection results.
―  If there is no malfunction:
•  Go to the next step.
No
Go to the next step.
2
VERIFY IF THERE IS THUMPING / RUMBLE OR GRIND SOUND
•  Is thumping / rumble or grinding sound present?
Yes
Inspect the following:
•  Drive belt tension
•  Loose parts in engine compartment
•  Loose heater hose bracket protector
―  If there is any malfunction:
•  Repair or replace the malfunctioning part according to the inspection results.
―  If there is no malfunction:
•  Go to the next step.
No
Go to the next step.
3
VERIFY IF THERE IS HISS SOUND
•  Is hiss sound present?
Yes
Inspect the following:
•  Vacuum leakage
•  Spark plug loose
•  Intake-air system leakage
―  If there is any malfunction:
•  Repair or replace the malfunctioning part according to the inspection results.
―  If there is no malfunction:
•  Go to the next step.
No
Go to the next step.
4
VERIFY IF THERE IS RATTLE SOUND
•  Is rattle sound present?
Yes
Inspect the location of rattle for loose parts.
•  If there is any malfunction:
―  Repair or replace the malfunctioning part according to the inspection results.
•  If there is no malfunction:
―  Go to the next step.
No
Go to the next step.
5
VERIFY IF THERE IS RAP OR ROAR SOUND
•  Is rap or roar sound present?
Yes
Inspect the following:
•  Dynamic damper installation
•  Exhaust system installation
•  Intake-air system installation
―  If there is any malfunction:
•  Repair or replace the malfunctioning part according to the inspection results.
―  If there is no malfunction:
•  Go to the next step.
No
Go to the next step.
6
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 [SKYACTIV-G 2.0, SKYACTIV-G 2.5].)
No
Inspect the following:
•  Electric variable valve timing actuator
•  Hydraulic variable valve timing actuator
•  Timing chain
•  Hydraulic lash adjuster (HLA) noise
•  Engine compression
―  If there is any malfunction:
•  Repair or replace the malfunctioning part according to the inspection results.
―  If there is no malfunction:
•  Go to the next step.
7
Verify the test results.
•  If normal, return to the diagnostic index to service any additional symptoms.
•  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.