Thanks for the tips on what to try fixing first to fix my hesitation problems. Turns out I went to change plugs, wires, cap, etc. and see that is has already been done. I just bought this jeep a week ago. Someone else has been chasing down this same problem. So that eliminates the first round of fixes. They also put a new coil on it.

I still get the hesitations under load since it doesn't do it all the time makes it more hard to track down. No check engine light on. I contacted the previous owner and she did tell me her mechanic tried all the typical things to fix it. He thought it might be the fuel filter inside the tank. She didn't want to pay for that so that's where it ended. The throttle body looked liked it had all been cleaned as well.

Any thoughts on if I should replace the fuel pump and filter?
Thanks again!

haven't done it-but the threads on here suggest that the "filter" in the tank is not a conventional filter. And that replacing the pump is about an hour and a half to two hour job-and not that difficult. If your spark is good (new ignition parts) and another mechanic is thinking pump/filter issues may be simple solution is to change fuel pump? It will also "fix" possible filter issue.

Only other "guesses" I got are-erratic voltage/alternator issue-or the computer? However those are just guesses - assuming all sensors are "good", and every thing else is "normal".

Let us know what it is when you find it!

Good Luck!

If I were you I'd get a fuel pressure gauge from some place like Harbor Freight or an auto parts store (they generally loan them) and check the fuel pressure first. Not sure what spec is on your 97 (it's 31psi on my 93) so you'll have to do some more searching or look at a manual to find out.

My 93 was sputtering and bucking at times and at other times would run just fine. I used the shotgun troubleshooting approach and threw lots of parts at it because I really didn't want to drop the tank to replace the fuel pump. In the end I had to do it anyway - because if the fuel pump's going bad it won't fix itself. IMO, its best to at least rule it out first by checking the fuel pressure.

I agree with this idea but if it is intermittent problem will it show low or poor pressure?

Check the O2 sensor, mine was bad and didn't show up on the dash-lights on my 97. It would hesitate, but not all the time, it was irritating as hell.

I checked the fuel pressure. However, it was idling fine then. But the pressure was normal about 47 psi. with key on (not running) Then was about 50 while running. I tried starting it several times to get it to idle rough but it never did. This is frustrating. I'm afraid it will leave me stranded if it's the fuel pump.

Thanks for the tip to get that checked.

If the fuel pressure is good (and like was said above it may not show bad all the time if the problem is intermittent - mine did but that doesn't mean yours will), then there are lots of other things to try. Oxygen sensor is as good a place as any to start because its easy to change out and they do historically go bad.

Incidentally, that's the first thing I replaced during my shotgun days - but I knew it was bad because it threw a code. My Jeep was trying to mess with my head so it ran really well for a couple of days after I changed it out so I thought that was the problem. Just when I called it fixed it started acting up again... I don't use the word fixed around my Jeep any more...

I just got my 02 TJ a day or two ago and I know that it needs an o2 sensor but not sure where to begin. Anyone with a quick "cliff notes" outline of where the thing is at would be appreciated.

Your Jeep is much newer than mine so keep in mind that my experience might not fit your situation. That said, my O2 sensor was on the exhaust pipe not far from the manifold. I ran the engine to heat up the exhaust to make the sensor easier to remove and then unplugged it and used a box end wrench to remove it. Did the opposite to replace it.

If you are going to try and work on your Jeep (like most of us) and you don't have much knowledge of how to do it (like me) then i would suggest you get a Chilton's or Hayes manual that covers your model. Both have lots of illustrations and how-to instructions and make for some great bathroom reading...