Misfire In One Cylinder

[PO3O1] The scan tool indicates Diagnostic Trouble Code (DTC) PO3O1: Cylinder 1 misfire detected.


[PO3O2] The scan tool indicates Diagnostic Trouble Code (DTC) P0302: Cylinder 2 misfire detected.


[PO303] The scan tool indicates Diagnostic Trouble Code (DTC) P0303: Cylinder 3 misfire detected.

[PO3O4] The scan tool indicates Diagnostic Trouble Code (DTC) P0304: Cylinder 4 misfire detected.

[PO3O5] The scan tool indicates Diagnostic Trouble Code (DTC) P0305: Cylinder 5 misfire detected.

[PO3O6] The scan tool indicates Diagnostic Trouble Code (DTC) PO3O6: Cylinder 6 misfire detected.


Description
Misfire detection is accomplished by monitoring the crankshaft speed with the crankshaft position sensor which is attached to the crankshaft.
If misfiring strong enough to damage the catalyst is detected, the MIL will blink during the time of its occurrence, and a
misfire DTC will be stored. Then, after the misfire has ceased, the MIL will come on.
If misfiring that increases emissions is detected during two consecutive driving cycles, the MIL will come on, and a misfire DTC will be stored.

NOTE: If some of the DTCs listed below are stored at the same time as a misfire DTC, troubleshoot those DTCs first, then troubleshoot the misfire DTC.

PO1O6: MAP sensor
P0171, P0172: Fuel supply system
PO4O1, P1491, P1498: EGR system
P0441: EVAP incorrect purge flow
P1359, P1361, P1362: TDC sensor
P1381, P1382: CYP sensor

Possible Cause
^ Fuel injector: clogging, fuel leakage, air leakage
^ Fuel injector circuit: open or shorted
^ Injector resistor: malfunction
^ Spark plug: carbon deposits, fouling, malfunction
^ Ignition wires: open, leaking
^ Distributor: malfunction
^ Compression: low
^ Valve clearance: out of spec