Hello. I have an abundance of codes on my 4.0 regarding misfiring and the O2 sensor and evap sensor. I was wondering if these are related? I did some research and my guess is that it is the broken O2 sensor. I've already replaced the engine because of a previous misfire issue because of the timing chain, I'm hoping that's not the case this time
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have you replace the O2 sensors?

 

What docm said... on my brothers truck had the same exact problem and the 02 sensor fixed the misfires