cadmanaz

I'm not mechanically inclined, so please take my question with a grain of salt...

My JK is pretty much stock.

Lately (for the last few weeks) my engine seems to "miss". I don't really know what an engine sounds or feels like when it's missing. If I can guess, I would say that "missing" has something to do with the spark plugs.

But, sometimes when I'm idling at a stop light, I can feel through the slight vibration that there's a slight shudder with the engine - and it's only happened once or twice a week for the last few weeks. It also seems to happen only after I've been driving it a while - not right after start-up.

I don't wheel much mainly washboard roads and some rock outcroppings (I disco the front every time); we don't have much water - except now with the monsoon storms; and I've had the stealership maintain it (lube/oil/filter) every 3k miles; it has a little over 12k on it.

My other thought is that it could be engine mounts.

Any thoughts?

EDIT: The shudder does not last more than a split-second... but it's noticable that the RPM drop very slightly. Also, under normal driving, there's no issues - it's never stalled nor accelarated slowly; always starts-up good, etc.

pearl-drum-man

Just food for thought, maybe it's not the engine but the tranny (if you have an auto). Look at this TSB and see if it helps you out:

http://project-jk.com/jeep-jk-tsb-re...-upshift-bumps

JK-Q8

I get it from day one, and was at the dealer a few times and its normal they say and my nephew has it on his jk too.

cadmanaz

x2. Mine only happens at idle. That TSB looked like it specifically stated it happens while in motion.

cadmanaz

Forgot to add that my JK is auto tranny.

Offroadme

mine sometimes does that. i feel sometimes that it is hesitating. i have a 6spd so i know its not the same problem the manual is having. i was going to try and swap out the plugs and see if that does anything.

ResQGrnRubi

Just to chime in, mine does it too, more likely to happen when hot after 30 mile highway drive coming home from work, then sitting at the light at the top of the off ramp..

cmpmacchia

Guess what me too. It only happens at a stop light and typically when the temp gauge is around the ¼ mark. If anyone swaps plugs for something aftermarket and it works please let the rest of us know. Its really not a huge issue though.

HarryBallz

Me too, and I have a manual. Just started to notice it a few days ago. I have about 2500 miles on the odometer.

mikejwil

Mine has never done that. I'd get it checked out right away... There is a spark plug TSB (very limited # of JKs) and also a "stall bug" TSB you guys may fall under.