Cracked coil pack bar

[bigmike441]

Hi, i have a 2000 xj, late last year i had to replace the coil pack bar because it had cracked, on the middle pack, well this past May it happened again, i have replaced it 3 times! it keeps happening in the exact same spot time after time, i dont know what to do everyone i talk to says its the part but i think theres something more going on. these packs arent cheap at 100 a piece. I NEED HELP ASAP

[bigmike441]

BTW it cracked again and died on me last night i had to have it towed home

[bluedragon436]

Sounds like it is either getting torqued down too much stressing the plastic, or that the standoffs that it bolts down too might be too high in the middle or something... I know I did the plugs and reinstalled the coil packs on a friend's TJ, and it seemed pretty straight forward, and not much that can cause them to keep cracking... but I don't remember if the standoffs in the middle are removable, and thus might be a bit too high..

[4.3LXJ]

Not sure what to say here as I am not familiar with those. But take some good pics of it as it is now and post them up and we will see if we can figure out something

[bigmike441]

the crack is on top of the middle pack, the pack is about 3 inches long 1 inch wide and about 1.5 tall, it has a section in the middle that is raised about .5 inch that runs from one side to the other, it cracks where the raised sections curves, i will take a picture in a little when i get home, it cracks here the red line is just on the middle one

[4.3LXJ]

Any codes and check engine light?

[bigmike441]

mis fire on cylinder 3 & 4, O2 sensors, before it cracks it runs very rough deff a misfire then it cracks, once i replace it the only code is the O2 sensors

[slvmart]

I'm with Bluedragon. It sounds like the pack is being installed and is under stress. Is there any difficulty with the installation of the pack ?

[bigmike441]

no its very simple, 4 bolts and a plug, the bolts holes are lined with metal, ill try to find a pic of the other side that shows the holes, never mind the pic i posted shows the hole