Engine Noise [SKYACTIV-G (Us)]: Notes

ENGINE NOISE [SKYACTIV-G (US)] DETECTION CONDITION AND POSSIBLE CAUSE

Troubleshooting item	Engine noise
Description	Engine noise from under hood.
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 Pulsing sound is heard: Exhaust shutter valve malfunction (With cylinder deactivation) 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 Tappet noise Hydraulic lash adjuster (HLA) noise
Possible cause	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 [SKYACTIV-G (WITH CYLINDER DEACTIVATION (US))] .) (See BEFORE SERVICE PRECAUTION [SKYACTIV-G (WITHOUT CYLINDER DEACTIVATION (US))] .) 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 [SKYACTIV-G (WITH CYLINDER DEACTIVATION (US))] .) (See QUICK RELEASE CONNECTOR (FUEL SYSTEM) REMOVAL/INSTALLATION [SKYACTIV-G (WITHOUT CYLINDER DEACTIVATION (US))] .) (See AFTER SERVICE PRECAUTION [SKYACTIV-G (WITH CYLINDER DEACTIVATION (US))] .) (See AFTER SERVICE PRECAUTION [SKYACTIV-G (WITHOUT CYLINDER DEACTIVATION (US))] .) 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.
System wiring diagram	Not applicable
Connector diagram	Not applicable