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

POSSIBLE CAUSES OF KNOCKING/PINGING-ACCELERATION/CRUISE

13

KNOCKING/PINGING - ACCELERATION/CRUISE

DESCRIPTION

Sound is heard when air/fuel mixture is ignited by something other than spark plug (such as hot spot in combustion chamber).

POSSIBLE CAUSE

Engine overheating due to cooling system malfunction
ECT sensor malfunction
IAT sensor malfunction
MAF sensor malfunction
Knock sensor malfunction
Erratic signal from CMP sensor
Inadequate engine compression
Inadequate fuel pressure
WARNING:
The following troubleshooting flow chart contains the fuel system diagnosis and repair procedures. Read the following warnings before servicing the fuel system:
- 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 injuries or death and damage. Fuel can also irritate skin and eyes. To prevent this, always complete "BEFORE SERVICE PRECAUTION" and "AFTER SERVICE PRECAUTION".
  (See BEFORE SERVICE PRECAUTION .)
  
  (See AFTER SERVICE PRECAUTION .)
CAUTION:
- Disconnecting/connecting quick release connector without cleaning it may cause damage to fuel pipe and quick release connector. Always clean quick release connector joint area before disconnecting/connecting, and make sure that it is free of foreign material.