Misses bad worse as warms up. Couldn't find previous post and thread. Update have repaired harness to downstream O2. No joy. Replaced PCM no help. Cranks funny when starting but idles smooth. Then misses both ways when throttle added.

 

I found your original thread. If you go to your profile and look in your stats, it's under "threads started".

https://www.cherokeeforum.com/f2/hard-miss-261293/

Those codes make it seem like you have a harness issue. Another user already recommended you replace the engine harness. At the very least, look for rubbed wiring around the rear of the cylinder head. It's very common.

 

Thanks. Can I order an engine harness?

 

Please change your profile. I doubt seriously you own a 2021 XJ 4.0

 

Year(s) of my XJ correct.

 

Found wires shorting harness side of connector to distributor. Cleaned and taped. No joy.

 

Found wires shorting harness side of connector to distributor. Cleaned and taped. No joy.

 

Take a look at the harness side connector of the crank sensor. peel back the convolute and check for insulation deterioration

 

Thanks was my next step! Will post results.

 

If they were shorting, have you checked for blown fuses after your repair?