So in the 2002 WJ with the 4.0l straight six, while the wife was driving, she had the check engine light come on. P0306 was the code, so I figured what the hell, I’ll switch it with #3 and see if it’s the plug or the coil pack. So after switching, resetting, and checking the coil packs’ ohm ratings, taking it for a spin, the check engine light comes back on, and I feel it not running right. Then it got more fun and the check engine light started flashing on the way back, along with the Part time light going on and off randomly. Got home, checked the codes and now have P0303 and P0837. (Instant embarrassing facepalm)I never went anywhere near the undercarriage where that switch is at. Is that electric plug on the coil pack somehow related? Any help is appreciated. Thanks in advance if there is any advice out there!
PS Spark Plug 3 seems like the easy part. I don’t believe it is the fuel injectors or coil pack due to the and stethoscope and ohm rating test for each.
Last edited by Uber_RT; 07-08-2019 at 07:22 PM.