HELP!!! 4.0 missing (skipping)

I have a 89 xj that Ive put plugs plug wires dis.cap and rotor button on trying to get rid of a skip (miss) Its not doing it all the time its doing it spuratically.It reminds me of a sensor going out Are there any way to pull codes out of the ecm to see what is going bad that needs to be replaced.

Sounds alot like my 89 MJ. I replaced the ignition parts last year when I had a true miss and fixed it. It developed a problem last week, more like a fuel thing and would "skip" while driving, mostly after warming up. Felt like it was cutting out momentarily. I cleaned out the throttle body and the IAC with a can of carb cleaner and cured it. Might give that a try. Sorry, can't help with the codes. Good luck.

This did start right after I filled up with gas on Thur.It had a small miss due to it not being tuned up so I did it hoping to cure the problem.

87's to 89's were knowned for having this problem. sometimes its ignition crossfire. if you have never reindexed your distributor, you might want to try it. there are many write ups on this site.

Quick test... Plug and unplug your CPS back right corner of your Valve cover. My waggie starts every time but would miss/skip sometimes while driving. Hasn't done it again in the last 3 weeks since i did that. So I know my CPS is going out at the connector more likly. HTH!!!

Ok it has got worse.driving home last night it has started back firing out of the throttle body .Shut it off and when I got it towed home tried to start it and now all it will do is pop back out threw the dis.but not start