if you get the Bosch or E3 there is no gapping required and all of the plugs are easy except for the rear one on passenger side is a little tough, dont bother changing the wires since you can only get them from the dealer now, no aftermarket wires available.

with only 15k on it though and stock I would consider taking it into the dealer if its doing it enough for it to happen while its there otherwise you will get could not duplicate and they'll just give it back

 

that's the thing, I can't even predict when it's gonna happen. It's pretty random, but it has happened about 5 times in the last 2 weeks. I've been driving a lot with summer here finally. I really doubt it'll do it for them. With only 15000 I don't need to worry about the plugs breaking off in the heads doing it myself, do I? (that's all I need)

When you guys said sparkplugs I got to thinking: In our town the cheapest gas station sells the 89oct midgrade cheaper than the 87oct gas, so that's what I had been using. Did I fowl the plugs by running fuel that's too rich on a regular basis? (like most of the last 15,000 miles)

 

The octane is not a factor in what you are experiencing. More likely they are selling it cheaper to get rid of it because it is old, or otherwise bad gas.

 

I don't think it's that. Casey's often does that depending on location because of the ethanol content. If you think about it, they're not selling as much gas (because of the ethanol content) and ethanol is gov-subsidized, so it's cheaper for them to sell (I believe it's up to 10% ethanol).

 

x2 - - - I steer clear from any "no name" fuel. For whatever reason, BP and Shell seem to burn fine for me, so its worth the extra 2 cents a gallon.

My tip on changing the plugs is to place the hood all the way back on the windshield so you can get in there....made it a lot easier for me. Also, passenger rear is the worst, yet drivers side is a breeze. I thought it was easiest to pull the wire support bracket and vacuum line support bracket off the valve cover studs - - gave more access to the rear plug and took 1 min to remove and replace. Finally, some people recommend anti-seize for the threads. The e3 website had so many disclaimers against it that I chose not to use it, but I did use a torque wrench at 15lbs to prevent overtightening.

 

Does their regular not have ethanol?

 

I'm honestly not sure, but the up to 10% ethanol is posted on the 89oct. It's usually 10 cents cheaper and the pumps are really fast. Our Shell station is the slowest pump I've ever been to. It really sucks. I would fuel my bike there because their premium was the highest octane around, but I avoid fueling the JK there.

 

About the rough idol,

I had this on my 07, started at 15,000 miles. Had throttle light coming on as well. It is
a red light with a lightning bolt. Not sure about the ESP light. Dealer replaced throttle
body and it went away with no problems since.

I also replaced plugs at 30,000 and this made the idol even smother than the day I got it.

 

Was yours bad enough the dealer saw it doing it? Because mine is really sporadic, and I don't think it'll do it for them. We also just moved two hours away from where we bought/I like to get it serviced at and I'm trying to decide where I'd like to take it to.

 

I’m not sure if it actually occurred while the dealer had it, but I believe there was a record of the electronic throttle control malfunction light coming on.

The rough idle came on suddenly and would shake the Jeep when stopped at lights. I'd say it was similar to a repeated misfire or when my distributor when bad on the Cherokee.