I started having issues with my xj so I decided to give it a tune up. It seemed to be running fine but then it started sputtering again. Here a list of parts I changed so far.
plugs, wires cap, rotor fuel and air filters.
Any suggestions on what else I should be looking at?
I also added some ground cables from batt to fire wall and from fire wall to intake manifold.
Thanks for your help.

 

Sputtering when you have the throttle in a certain spot or completely random?

 

At idle. If I try to drive it, it will pick up speed but runs like crap and when I come to a stop it wants to die.

 

I would test the TPS and IAC. If you've never cleaned the throttle body I recommend doing that as well. Test first then clean.

 

Actually I forgot to mention that I took the throtle body off and gave it a good cleaning as well as the IAC. I have yet to try the TPS. Would a bad fuel pressure reg cause any problems?

 

Well...you could look, listen for vacuum leaks. Also the little tube up to the MAP sensor up on the firewall needs to be perfect.

Any smoke, smell gas? Do you drive it?, on the highway? What did the old plugs look like? Got a digital meter?

 

Very lil smoke. I smell a lil bit of gas and exhaust fumes. Last time I drove it was after the TB cleaning, I drove it to work and back(highway round trip of about 36 miles). When I drove it, it felt fine at first but by the time I got to work I noticed it would bog when I stabbed the throttle. If I rolled into it, it would pick up speed with very lil sputtering. On my way home it felt fine once more till I got off the freeway, it started sputtering like crazy and wanted to stall at every stop. My old plugs looked normal to me(they were E3's that had been in there for about a year). Yes I have a digital meter but not very knowledgeable on how to use it.