I have an 07 X, stock 3.8l that's throwing the P0302 with a rough idle. It doesn't shake as bad when I start it up but once in gear she gets the shakes in all gear positions. Here's a video I posted: h ttp://youtu.be/Ev3KfbxnvLk
I replaced the spark plugs with OEM Champions as well as the wires. Anyone else go through this? I'm aware of the issue with the 3.6l's

 

The wife had p0300 multiple cylinder misfire. Thew a bunch of parts at it, finally took it to the dealer and found out the cat's were clogged.

 

Weak. I also had a guy tell me left side cylinder. Since it's used I probably don't fall under the warranty for cats. I'm finishing up the suspension and it'll probably head to the mechanic. I'm using the WJ now, needless to say I'm envious every time I see a wrangler on the road

 

I do believe emission components have a different warranty coverage. Look for more info on this.

 

I believe catalytic convertors are warranted for 80K miles.

 

From the 2007 warranty booklet:

B. Parts Covered for 8 years or 80,000 miles
If your vehicle has one of the following parts, this
Federal Emission Warranty covers that part for a
period of 8 years or 80,000 miles, whichever occurs first.
These limits are counted from the time when your
Basic Limited Warranty begins under 2.1(E). The
covered parts are:
• catalytic converter; and
• powertrain control module.

 

Thanks guys! I replaced the coil pack and so far no issues! I just need to finish putting the suspension back together and bring her for a test run. I'd like to add Joe at Teraflex has been very helpful with the suspension side and betted on a bad coil with the cylinder misfire. +1 to Teraflex
Thanks again for all the info guys.