Engine Noise: Outline

ENGINE NOISE (SKYACTIV-G) DESCRIPTION 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 incorrect installation Exhaust system incorrect installation Intake system incorrect installation Squeal, click, or chirp noise: Improper engine oil level Solenoid valve incorrect installation Improper drive belt tension Generator incorrect 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 Spark plug incorrect installation Air leakage from intake-air system Clattering noise: Loose parts Lightly tapping or rumbling noise: Dynamic damper incorrect installation Exhaust system incorrect installation Intake system incorrect installation 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. (Refer to BEFORE SERVICE PRECAUTION [SKYACTIV-G 2.0] in service information.) 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. (Refer to QUICK RELEASE CONNECTOR REMOVAL/INSTALLATION [SKYACTIV-G 2.0] in service information.) (Refer to AFTER SERVICE PRECAUTION [SKYACTIV-G 2.0] in service information.) 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