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

NO. 13 KNOCKING/PINGING-ACCELERATION/CRUISE REFERENCE CHART (MZI-3.7)

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 IAT sensor malfunction MAF sensor malfunction PCM DTC is stored Inadequate engine compression Erratic signal from CMP sensor Erratic signal from CKP sensor Inadequate fuel pressure Intermittent open or short circuit in fuel pump circuit Fuel pump mechanical malfunction Fuel line restriction or clogging Pressure regulator malfunction (built-in fuel pump unit) KS malfunction Improper ignition timing Poor fuel quality (i.e. Fuel RON is not specified, excessive cleaning agents added in fuel. 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" described in this service information. (See BEFORE SERVICE PRECAUTION article.) (See AFTER SERVICE PRECAUTION article.) 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.

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
IAT sensor malfunction
MAF sensor malfunction
PCM DTC is stored
Inadequate engine compression
Erratic signal from CMP sensor
Erratic signal from CKP sensor
Inadequate fuel pressure
- Intermittent open or short circuit in fuel pump circuit
- Fuel pump mechanical malfunction
- Fuel line restriction or clogging
- Pressure regulator malfunction (built-in fuel pump unit)
KS malfunction
Improper ignition timing
Poor fuel quality (i.e. Fuel RON is not specified, excessive cleaning agents added in fuel.
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" described in this service information.
    (See BEFORE SERVICE PRECAUTION article.)
    
    (See AFTER SERVICE PRECAUTION article.)
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.