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No. 13 - Knocking/Pinging-Acceleration/Cruise: Notes

NO. 13 KNOCKING/PINGING-ACCELERATION/CRUISE 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.