P0306 Cylinder 6 Misfire

P0306 Cylinder 6 Misfire - When monitored, with the engine running, the adaptive numerator has been succesfully updated. Set conditions, the variation in crankshaft speed between each cylinder exceeds a calibrated value, based on engine rpm load. Default actions, the MIL light illuminate.

Possible causes:

• ASD relay output.
• Injector control circuit.
• Coil control circuit.
• Ignition wire.
• Spark plug.
• Ignition coil.
• Fuel delivery system issue.
• Fuel injector.
• Engine mechanical.
• Powertrain Control Module (PCM).

Diagnose code P0306 Cylinder 6 Misfire

(Sorry!!! Step 1-2, refer to code P0301)
Step 1. Check active DTC

Step 2. Visual Inspection

(Sorry!!! Step 3-5, refer to code P0302)
Step 3. Ignition system operation

Step 4. Spark plug

Step 5. Fuel pressure check

(Sorry!!! Step 6-8, refer to code P0303)

Step 6. Fuel pressure leak down

Step 7. Fuel injector operation

Step 8. Engine mechanical

(Sorry!!! Step 9-11, refer to code P0304)

Step 9. Fuel injector control

Step 10. Injector control circuit

Step 11. Fuel supply line restricted

(Sorry!!! Step 12-14, refer to code P0305)

Step 12. Fuel pump inlet strainer

Step 13. ASD relay output circuit

Step 14. Ignition coil

Step 15. Coil control 6 circuit shorted to ground

Turn the ignition off, disconnect the PCM harness connector. Measure the resistance between ground and the coil control 6 circuit in the coil on plug harness connector.

Is the resistance below 100 Ohms?

Yes, repair the short to ground in the coil control 6 circuit.

No, go to step 17.

Step 16. Coil control 6 circuit open

Turn the ignition off, disconnect the PCM harness conenctor. Measure the resistance of the coil control 6 circuit from the coil on plug harness connector to the PCM harness connector.

Is the resistance below 3.0 Ohms?

Yes, go to step 17.

No, repair the open in the coil control 6 circuit.

Step 17. Powertrain Control Module (PCM)

Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the ignition coil and Powertrain Control Module (PCM). Look for any chafed, pierced, pinched, or partially broken wires. Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the ignition coil and PCM connector. refer any Service Bulletins that may apply.

Were there any problems found?

Yes, repair as necessary.

No, replace and program the Powertrain Control Module (PCM). Perform the Powertrain Verification Test.

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