Good morning, this is my first time on this forum or any forum for that matter. Not sure how this is supposed to work but I came here looking for a solution to a problem so here goes.


I have a 2007 Wrangler JK, I think the model is the unlimited. It started misfiring awhile back and I changed the the plug, plug wires and coil pack. It ran right for awhile but it started again. 3/29/21 I bought another coil pack, from the dealer, and changed the plug wires again and it's still misfiring. This morning I pulled the plug wires from the coil pack one at a time and found the #2 and #5 pole on the coil pack were not firing. People, that think they know about working on vehicles, told me, it has to be the coil pack. Even after I changed it a second time. After putting a third coil pack, from the dealer on, I'm pretty sure its not the coil pack. So as it stands now, my jeep is misfiring, or not firing and I have a P2305 code. If anyone has ever experienced a problem like this or has an idea of what the problem might be, I would really appreciate your input.

 

Welcome. Hard to diagnose over the internet. Check all grounds, battery condition, ECU plugs good connections, could be ECU, could be trigger wiring from ECU to the coil pack. Get wiring diagrams if you can and start looking and stop spending for a while. Don't you wish we still had distributor and carbs?

 

so this is harder if you have more than 2 cylinders misfiring, but if you're currently just getting the #5 misfire, the easiest thing is to swap that coil pack with a different cylinder and see if the misfire moves. If the misfire moves to the new cylinder then the coil pack is bad. If the old cylinder continues to misfire then it's not a coil problem.