P0304 Code & ETC Warning Light
My check engine light came on as well and I brought it to the dealership, they told me misfire on #4. Service guy told me that this is a known issue and a need the head replaced for those cylinders, having work done this week. He said oil burn and rough idle is common with this issue. I have 25k on mine. I'll let you know how it goes.
Thanks. My CEL has gone off and it has been running great all day. I planned on replacing the spark plugs tomorrow, but now I'm wondering if I should just bring it in and have them go through the hoops to see what the real underlying problem is, if any at all.
The dealership just called back and confirmed the cylinder 4 misfire. They are going to change the spark plugs, update some computer module, and reset the CEL for $212. As far as the loss of oil, they recommended a carbon flush at the time of my next oil change. They also said my PCV valve was fine.
Last edited by Hack12; Jan 28, 2013 at 08:32 AM.
Alrighty, so got my Jeep back from the dealer and everything seems fine. It's been a couple of days and so far there has been no sign of a returning CEL. The dealership only changed the spark plugs and updated the PCM.
However, I am noticing a slight tremble just before I come to a stop, when the RPM's are at their lowest. It idle's perfectly though, no roughness. I can't remember it doing that before. Any thoughts would be greatly appreciated.
However, I am noticing a slight tremble just before I come to a stop, when the RPM's are at their lowest. It idle's perfectly though, no roughness. I can't remember it doing that before. Any thoughts would be greatly appreciated.
Last edited by Hack12; Jan 30, 2013 at 06:20 AM.


