P0305 Cylinder 5 Misfire

P0305 Cylinder 5 Misfire - When Monitored DTC P0301 Cylinder 5 Misfire, this diagnostic runs continuously when the following conditions are met, with the engine running, the adaptive numerator has been succesfully updated.

Set conditions P0305 code, the variation in crankshaft speed between each cylinder exceeds a calibrated value, based on engine rpm load.

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 P0305 Cylinder 5 Misfire

(Sorry!!! Step 1-2, refer to code P0301)
Step 1. Check for an 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

Step 12. Fuel pump inlet strainer

Turn the ignition off, remove the fuel pump module and inspect the fuel inlet strainer.

Is the fuel inlet strainer plugged?

Yes, replace the fuel pump inlet strainer.

No, before continuing, check the fuel pump module harness connector terminals for corrosion, damage or terminal push out. Make sure the ground circuit is functional, reapir as necessary. Replace the fuel pump module.

Step 13. ASD relay output circuit

Turn the ignition off, disconnect the coil on plug harness connector. Turn the ignition on, with the scan tool, actuate the ASD relay. Using a 12-volt test light connected to ground, probe the ASD relay output circuit in the coil on plug harness connector.

Does the test light illuminate brightly?

Yes, go to step 14.

No, repair the open or short to ground in the ASD relay output circuit.

Note: Stop all actuations.

Step 14. Ignition coil

Using a 12-volt test light connected to a 12 volt source, probe the coil control 5 circuit. Crank the engine for 5.0 seconds while observing the test light.

What is the condition of the test light while cranking the engine?

Brightly blinking, replace the ignition coil.

On constantly, go to step 15.

Off constantly, go to step 16.

(Sorry!!! Step 15-17, refer to code P0306)
Step 15. Coil control 5 circuit shorted to ground

Step 16. Coil control 5 circuit open

Step 17. Powertrain Control Module (PCM)

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