Recently took the ol XJ to get inspected but on the way to the garage it threw a check engine light. I hooked it up to my little scanner and read the code which came up Misfire on number 6 cyl. Most guys posts have a number 3/4 cyl misfire due to heat soak but i havent heard of anyone getting a number 6 cyl misfire. I tried running injector cleaner through it but nothing. Every injector fires as you can feel them and they have a slight tick to them (normal? I dont know). Im going to do plugs in it (NGK copper core) thats what everyone says. Anything else to check? Its a 98 and has 128,000 on it and the head is probably not cracked (oil was just changed and was good, temp runs a hair below 210, coolant is good). It probably has the 0331 head on it. Any input would be helpful, Thanks guys

 

tic is normal for the injector. have you checked spark on that cylinder? Probably dont have a 0331.
2686 - 1987-1990 242ci
7120 - 1991-1995 242ci
0630 - 1996-2000 242ci
0331 - 1999-2006 242ci
you can check though by looking between the 3rd and 4th intake ports on the head.

 

I can tell you anything about a small block chevy but im not to fond of a 4.0 jeep because i havent played with them much. but thanks on the injector info. Im going to check the spark now and probably buy a set of plugs

 

Sorry, i thought the info on the heads was part of your signature at first glance haha, thanks again im gonna go have a look now and see what i can come up with

 

lol. keep us updated. and i didnt know jack about the 4.0 either when i got my jeep. just keep reading and youll eventually learn enough.

 

replaced all 6 plugs and number 6 cyl plug, the electrode was cracked so that was my ploblem. dumb i know

 

always like an easy fix.