1994-2002 [Subscribe to Daily Digest] |
2. Engine\Trionic O... Fault diagnosis, fa...
P0300
Misfiring, randomly in several cylinders.
Symptom of fault
The CHECK ENGINE lamp (MIL) is on or flashing. Uneven running
when misfiring.
Conditions
An engine load and speed dependent matrix in the electronic
control module's memory specifies how large a proportion of
misfires is required for exhaust emissions to reach prohibited
limits or for the three way catalytic converter to be damaged.
If the number of misfires exceeds the matrix value, a diagnostic
trouble code will be generated. Misfiring occurs in several
cylinders.
Diagnostic help
The cause of misfiring could be:
• Low fuel level in the tank. If this is the case it will be
indicated by diagnostic trouble code P1416 also being
generated.
• a fault in the fuel system
low fuel pressure
purge valve open continuously
incorrect voltage from front heated oxygen sensor
defective injectors
• a fault in the ignition system
defective spark plugs
defective ignition discharge module
• a fault in the basic engine
poor compression
• faults in common components - pressure sensor - main relay
- coolant temperature sensor.
The cause of incorrectly detected misfiring, diagnostic trouble
code P0300 without misfiring, could be:
control module pin 17 or 18 shorted to ground
Enjoy!
--bazil
'85 SPG
posted by 24.52.17...
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