Error P0306 – how to fix?

Hi!,good morning. In this article you will discover a description of fuses and relays Error P0306 – how to fix?

Include with photos of block diagrams along with their locations. Highlighted the cigarette lighter fuse (as the most used thing people look for).
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Code definition P0306

Cylinder 6 Detected with Misfire

What does the code P0306 mean?

P0306 is the general OBD-II code which indicates that the engine control module (ECM) has detected a misfire on engine cylinder 6.

What causes the code P0306?

  • Spark plug does not ignite in cylinder # 6 due to dirt or crack in the insulation.
  • The ignition coil for cylinder # 6 stopped igniting due to cracked insulation or an open circuit.
  • Due to age, the spark plug wire or spark plug cover has a jump from the ignition spark to ground in cylinder 6.
  • Valve cover has an oil leak at the spark plug holes and a spark plug ignition short for cylinder # 6.
  • The cylinder has problems with low compression due to faulty rings or valves.

What are the symptoms of the P0306 code?

  • The Check Engine light will come on and the code will be stored in the ECM’s memory.
  • The Check Engine Light will flash when a misfire occurs.
  • The engine will not fire and may jerk or jolt when accelerating.
  • The engine will be de-energized during acceleration while the misfire is active and may affect gear shifting.

How can a mechanic diagnose the P0306 code?

  • Scan the codes and document the data from the frozen frame to verify the problem.
  • Clear engine codes and ETCs and road test to verify problem does not recur.
  • Remove the ignition coil from cylinder 6 or spark plug wire and inspect the outside of the coil or spark plug housing for traces of a spark. You should also pay attention to oil contamination through a leaky valve cover.
  • Remove spark plug from cylinder number 6 for inspection and replacement if necessary.
  • Check engine cylinder compression if no ignition problems are found.

The most common errors when diagnosing the code P0306

  • Do not move the coil to a different cylinder to see if the misfire has transferred to another cylinder. This would indicate a damaged coil.
  • Do not replace one part at a time with another cylinder to isolate the damaged part.

How serious is the P0306 code?

  • A misfiring cylinder can make the engine run too rich and may damage the catalytic converter.
  • A misfire will cause the engine to run rough and hesitate when accelerating.
  • The engine will use more fuel due to the misfire.

What repairs can fix the code P0306?

  • Replace faulty spark plug, or replace all spark plugs together if the cause of the fault is a worn spark plug.
  • Replace the leaking valve cover gasket and then replace the coil, spark plug wires, and damaged spark plugs.
  • Replace the ECM with the wrong fuel injector supply circuit or coil for number 6.

Additional considerations regarding the consideration of the P0306 code

Code P0306 triggers when the crankshaft sensor does not receive crankshaft acceleration from the firing cylinder number 6 correctly, indicating that the cylinder is not contributing to engine power.

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