This is really driving me nuts. I take my jeep to a professional mechanic, spend 160 bucks for him to remove some weird valve cover blow by filter and install an O2 sensor. Jeep runs fine with no CEL for a day.

CEL comes back on with 3 more codes (p0300, p0301, p0302). Take it back to the shop and he finds faulty injector wires and repairs them($114). 4 days later CEL back on with codes (p0300, p0301). I'm taking it back to the shop but seriously what else is there to replace lol.

 

If you have a P0300 random misfire code, it means the misfire is random and is moving around from cylinder to cylinder. The cause here would likely be something that upsets the engine's air/fuel mixture, such as a major vacuum leak, or unusually low fuel pressure (weak pump or faulty pressure regulator). Look for a "common" root cause here and not something related to a single cylinder.

 

You would think with low fuel pressure it would cut in and out while driving... idk. My fuel pump is whining pretty loud maybe that is an issue?