NO. 13 Knocking/Pinging-acceleration/Cruise: Notes

NO. 13 KNOCKING/PINGING-ACCELERATION/CRUISE (SKYACTIV-G 2.5T) DESCRIPTION AND POSSIBLE CAUSE

13	KNOCKING/PINGING-ACCELERATION/CRUISE
DESCRIPTION	Abnormal combustion occurs under the condition such as the temperature in the combustion chamber is too high resulting in abnormal noise. Knocking sound occurs from the engine compartment during acceleration.
POSSIBLE CAUSE	Poor fuel quality Fuel RON is not specified Excessive cleaning agents added in fuel Poor connection of KS, wiring harness The following information for calculating ignition timing is incorrect: KS signal ECT sensor No. 1 signal IAT sensor No. 2 (integrated in MAP sensor) signal MAF sensor signal Air suction in intake-air system MAP sensor signal Boost pressure sensor signal Boost air temperature sensor signal Combustion temperature is high Cooling system malfunction Carbon accumulation Use of non-genuine spark plug 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 .) 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 Removal/Installation .) (See After Service Precaution .) 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.

KNOCKING/PINGING-ACCELERATION/CRUISE

DESCRIPTION

Abnormal combustion occurs under the condition such as the temperature in the combustion chamber is too high resulting in abnormal noise.
Knocking sound occurs from the engine compartment during acceleration.

POSSIBLE CAUSE

Poor fuel quality
- Fuel RON is not specified
  - Excessive cleaning agents added in fuel
Poor connection of KS, wiring harness
The following information for calculating ignition timing is incorrect:
- KS signal
- ECT sensor No. 1 signal
- IAT sensor No. 2 (integrated in MAP sensor) signal
  - MAF sensor signal
Air suction in intake-air system
- MAP sensor signal
- Boost pressure sensor signal
  - Boost air temperature sensor signal
Combustion temperature is high
- Cooling system malfunction
- Carbon accumulation
  - Use of non-genuine spark plug

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 .)
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 Removal/Installation .) (See After Service Precaution .)

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.