Jeep starts sluggish and then wants to die

Had this problem too, and you need to check that your TPS sensor plug.harness is tight, the best way to do that is to actually unplug it, blow it out and then plug it back in. But the same problem happened again and it turned out to be the CPS plug had come loose, again check it and make sure it's seated well, and everyone will tell you to replace them, but if take a wooden dole, or stick and can tap yours gently down towards the transmission I've found that it works well after that.

http://www.fototime.com/554D75F2A0D08B0/standard.jpg

hi there.
not sure if this link will help you out but have a look.
1991 Jeep Wrangler stall and die Google Search

Visit the on-line store, known as reliable-store, they have the repair manuals. I'm sure you will get the solution of your problem.
1999 Jeep Wrangler

Is this vehicle a stick or and automatic? based on your write up it sponds loke your popping the clutch to get it started. If thats the case you need a starter. If not then check the following:
Battery cables off the battery and starter ,starter relay and ignition switch. These are the items in the starting system for no crank and no start.
Get Shop manual and do the appropriate testing for each.

1. check for vaccuum leaks.
2. check for a check engine code
3. check the throttle body/butterfly plate for carbon build up.

yes the crank sensor is probebly your problem.

You need to check the fuel pressure, if not enough it will run rough.

Would Probably help if you Changed the Fuel Filter.

Try holding your gas pedal all the way down while starting.

get a 6 cylinder motor drop in this is best gas saver for most vehicles 4 cylinders dont have the ability to push all the weight of a vehicle but runs smoothly
6 cylinders are as i put in words are evenly balanced for everyday use and not gas guzzler either