likely cause of: engine code p0304, #4 cyl misfire; plugs & wires were replaced 2 months ago. vehicle passed an emissions test (Ontario Canada) last month (4,000 km ago) with readings of "0"!
Country: CanadaMake: ChryslerModel: PT CruiserYear: 2006Engine: 2.4L
check plug wire connections
Welcome to Just Answer Chrysler my name is Mark.If we assume the plugs and wires are still ok..........although they should be checked and tested.........then a misfire isolated to one cylinder will most likely mean either a compression problem with the #4 cylinder or a fuel delivery issue because of a bad injector.So. A compression test would need to be done, and then you can swap the #4 injector with another cylinder and then see if the misfire moves to the new cylinder, or stays with #4.
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