Bucking, Stalling, Rough Ride...

Hey all-
New to the forum, but not to Jeeps.
So here's my deal...went to start my XJ after work to go get something the other day and it would not start. Sounded like it was going to but wouldn't turn over.
Took my dog for a walk, came back and it fired right up.
Drove to work the next day, no problems. Coming home from work about 5 blocks frommy house my XJ started having low/irradic idle and then died at the intersection. Wouldn't start back up again. Same thing as the other day...sounded like it wanted to, but something wasn't letting it turn over, like it wasn't getting enough spark.
Had it towed to a service station since I didn't have time to poke around with it. They called and said the cap and rotor were shot, that makes sense based on what I was experiencing. They replaced those I picked it up and it ran just fine. Started ok, ran fine for a couple of days.
Well, last night driving to my fire station about 3/4 of the way there it started idiling kind of weird, and wanting to die. If I kept the RPMs up, it still ran rough as all hell but seemed to keep it from dying. It would also buck and sputter like it was running on 3 cylinders. Just super rough. If you mashed the gas, the transmission would shift like normal, but it's like it wasn't getting A) enough gas or B) not enough spark to the right areas.
Limped it to the fire station and shut it down...well I guess it stalled and shut itself down. Wouldn't start back up, just like the initial problems.
Let it sit for awhile (about 1 hr) and tried to start it. Fired right up, no rough idle or anything. Drove it around the block, nothing. Ran fine.
Went back to the fire station and turned it off.
When my shift was done I went out to my XJ, turned it on and proceeded to go home.
About 1/2 way home it started it's business again with the rough, rough running, bucking and almost stalling. Again, limped it home and shut it down. Haven't tried starting it yet today, but I'm sure it will fire up just fine.
I'm going to bring it to the shop since I don't have time or space right now to work on it, but do you all have any suggestions off hand?
Afer doing some research, I've heard this problem assc. with the CPS/MAP/IAC, maybe fuel pump, a bad gorund somewhere, or even the cat convertor. Long story short, I'd like to get the small stuff taken care of before I start spending all kinds of cash on something that won't remedy the problem.
Suggestions? Thanks..

BTT Any ideas?

When was the last time you did tune up?
What year do you have?
A clogged cat will usually glow red after you drive for 10-15 minutes.

It's a 96..last tune up about 2 months ago. It run smooth as silk when it's not trying to implode on itself..

could be temp sensors sending wrong signal to ECU ! !

I replaced the temp sensor about a year ago....after doing some research, this sounds a lot like a faulty CPS....any takers?

Have you replaced the plugs and wires since the new cap and rotor were installed?

No, but the plugs and wires are both in fine shape. I checked them both and they're not all that old.
The mechanic just called and said it was "just too wet"....?
Like there is too much moisture under the hood. He said it wasn't producing any codes, so possibly not a CPS....we'll see. I have a hard time buying into this because it has been much more submerged and much more wet than it is out right now and it's never done anything like this.
They said they'll be taking it out for another test drive to see if it will do it's sputtering/stalling/rough idle deal. I tried to explain a possible CPS and he said it would throw a code if that were the case. Is that true??
But you all know the deal....of course it will run fine for them and I'll get stuck on the side of the road tomorrow morning on my way into work.
Isn't that how it always works?:roflmao:

BlackXJ96 said:

No, but the plugs and wires are both in fine shape. I checked them both and they're not all that old.
The mechanic just called and said it was "just too wet"....?
Like there is too much moisture under the hood. He said it wasn't producing any codes, so possibly not a CPS....we'll see. I have a hard time buying into this because it has been much more submerged and much more wet than it is out right now and it's never done anything like this.
They said they'll be taking it out for another test drive to see if it will do it's sputtering/stalling/rough idle deal. I tried to explain a possible CPS and he said it would throw a code if that were the case. Is that true??
But you all know the deal....of course it will run fine for them and I'll get stuck on the side of the road tomorrow morning on my way into work.
Isn't that how it always works?:roflmao:

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Go buy a new set of wires and plugs(THEY ARE CHEAP!). They are not expensive and are usally the culprit. If your cap and rotor were bad more than likely the wires will be bad. You can not see aplug fouling out. Usally a person cant tell if a wire is bad by just looking at it.

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