Plemons x_jay

i have 96 xj. Recently, when i start it up, it will bog down and be very sluggish and stuttering, then after about 5-10 seconds, it will suddenly rev up to 2k rpms, then to regular idle speed. even at idle, it sounds like it has a big cam, and it studders.
last week, i went on vaction for a week, come back and get in it, it does its regular sluggish bogging start. i drive it for about 5 mins and come to a stop sign. i stop, then tap the gas as if i were taking off any other time, and it bogs down, almost dies, then the engine almost like catches, and then i take off. it did this for a day. it was low on gas so i was going to go to the store. it does the same thing over and over every time i stop for 10 mins. the last stop sign i get to before the gas station, it bogged down and died. i tried starting it, no budge. i called one of my buddies and he pulled me home. i got it home and tried starting it, the only way it would start was if i held the throttle wide open, and it would only hesitate to start then. i left it over night, got in it the next morning, and it started, did the bogging problem, then was fine. i tried backing it into the garage and it died again. i then put 5 gal of gas in it and left it overnight again. it started right up the next morning but still did the bogging when the gas pedal was pushed.
Ive got fellow jeepers telling me it the coil pack, the injectors, the intake filter, vaccum lines, ignition, etc. im needing to know what you guys think about it. im tired of guessing, i just want to know what it is and fix it. and it coulnt be the TPS because ive replaced it twice in the last year.

tgordon

Judging from your description of the symptoms, the fuel level has some bearing on the issue. So start trouble shooting there.
Check fuel pressure at the rail for the minimum per your manual.

Note: It is still possible to have a bad TPS. You have already had to change it twice, correct?

Turbo X_J

"and it coulnt be the TPS because ive replaced it twice in the last year."

why? What specific codes are active?

Plemons x_jay

yeah ive replaced it twice

Plemons x_jay

I think its the ect

redxj96

Is your jeep reading a good temperature for your coolant? If your temp sensor is telling the brain its running hot when it isn't then it will mess with your fuel distribution.

Roler

The symptoms you describe need a systematic approach since several things can cause this.
As was mentioned above, getting a fuel pressure gives you an idea of fuel delivery issue is in play.
Your 4.0 engine's CPS can cause this as well and at some point the CPS (crankshaft position sensor) will go out. Replace this with a quality one.
Do a tune-up if not done before, relatively cheap and on the things-to-do list.
Again, several things can be in play, but this could be a good start to go with.

Plemons x_jay

It was the etc. Blows my mind but whatever fixes it lol

F1Addict

What is an ETC?

CCKen

Etcetera.

Or....

Engine Coolant Temperature (sensor).