P0300 Random misfire:

When you have a “DTC” Diagnostic Trouble Code P0300, it is hard to pinpoint the problem that could cause this to happen. But no worries, we are here to give you all the knowledge you need to get this done right from the get-go.  The first most logical thing to do for this code is to pull all the coil packs, and inspect if there is any oil on them. If you see oil on any of the coils, then this is the problem that is causing the random misfire “cracked seal” on the valve cover.


When oil gets into the spark plug housing, it causes the spark to disperse. You lose power, causing you to have the sense of engine failure.


It is recommended that you change both valve covers, valve cover gaskets, and the PCV valve with the blow by hose. 

Components List:

  1. Valve Cover (right). Part number: 13264 - 7Y000  Retail: $123.32. 
  2. Valve Cover (left). Part Number: 13264 - 7Y010  Retail: $245.25.
  3. PCV Valve. Part Number: 11810 - 8J102 Retail: $22.40.
  4. Blow-By-Hose. Part Number: 11823 - 8J10A Reatil: $20.93.

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