DFORD90

My 2012 jku has this intermittent problem where it runs like I picked up water in the fuel. This lasts a day or so then clears up . The engine runs rough and check engine light blinks and dings while it happening . First time I tied dry gas seemed to clear it up then it happened 2 more times and I replaced the crank position sensor. Jeep was running amazing then driving down the road like somone flipped a switch back to rough idle and chugging along like pappy's Kubota 🤦‍♂️
I was thinking about doing the pcv valve next ? Any one solve this isse before? Any help or isight would be greatly appreciated!!

Sunnysideup

It could be a glitch. Mine ocassionaly does that... I pull it over turn it off for a couple min. Restart... and it runs normal. It only does it about twice a year... but when it does, lights flash and it chugs like its in a stumble. I think it is a short somewhere- I can never find it- but it happens very infrequently.

Ryan0260

Something we often trust too much and overlook is simply bad gas. Was talking to a mechanic friend of mine the other day and he said I wouldn't believe how many service calls with similar issues with bad idling etc are due to bad gas or gas with too much ethanol in it. Not saying this is causing your problem but definitely don't overlook it. Maybe change to a higher octane or brand if you tend to use the same places to fill up.

DFORD90

Quick update.. I pulled the plug for cylender 5 plug was nasty. Replaced plug and coil. ISSUE SOLVED! Untill it wasn't 😡🤬 lasted a month and went right back to running like complete sh*t ! Pulled the month old plud and it was fouled again.. it's only cylender 5 that's doing it. I ordered a PCV valve today im hoping its a bad PCV letting oil escape and fouling the plug ? Are there any other possibilities that can be fouling only the cylender 5 plug?? I'm hoping it dont have the notorious bad head