YJJPWrangler
Well-Known Member
- Joined
- Jul 19, 2005
- Location
- Charlotte
Wifes 2000 Grand Cherokee(4.7L) keeps throwing a cylinder 5 misfire. I pulled the spark plug and some of the porcelain was missing. Replaced plug, reset computer and after about 20 mins of driving it the CEL came back on again. I had the same issue with it last year and replaced the plug and the coil pack. Coil pack looked brand new when I put it back together. Anything else I'm missing? Could it just be a bad coil pack(again)? I also had to replace the upstream O2 sensor this weekend as well but that should affect anything.