Mazda RX8 - Knocking;Pinging;Detonation - Acceleration;Cruise

NO.13 KNOCKING/PINGING/DETONATION-ACCELERATION/CRUISE
13 KNOCKING/PINGING/DETONATION - ACCELERATION/CRUISE
DESCRIPTION
A sound is produced when the air/fuel mixture is ignited by something other than the spark
plug (e.g., hot spot in combustion chamber).
POSSIBLE
CAUSE
• Air suction at intake-air system
• Poor fuel quality
• Inadequate fuel pressure
• Pressure regulator (integrated in fuel pump unit) malfunction
• Fuel pump relay stuck closed
• Fuel injector malfunction (clogging, lack of injection amount)
• Erratic signal from eccentric shaft position sensor
• Improper ignition timing control (ECT, IAT, MAF and knock signals to PCM)
• Incorrect spark plug heat range
• Improper operation of eccentric shaft bypass valve
• Engine overheating due to cooling system malfunction
• Excessive carbon is built up in combustion chamber
• Inadequate engine compression
! Engine internal malfunction
! Abnormal engine oil condition (viscosity, deterioration)
! Low oil pressure
! Excessive fuel pressure
! Air mixed in oil malfunction
! Metering oil pump malfunction
• Leakage or clogging in oil pipe
• Leakage or clogging in oil nozzle
WARNING: The following troubleshooting flow chart contains 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 REPAIR PROCEDURE" and "AFTER REPAIR
PROCEDURE" described in this manual.
(See BEFORE REPAIR PROCEDURE
.)
(See AFTER REPAIR PROCEDURE .)
CAUTION:
• Disconnecting/connecting quick release connector without cleaning it may possibly
cause damage to fuel pipe and quick release connector. Always clean quick release
connector
j
oint area before disconnectin
g
/connectin
g,
and make sure that it is free of
(w) RX8-Engine Troubleshooting
Page 98