2001 jeep Cherokee 4.0, rough idle, when taking off from a stop, just at 3000 RPM it starts bucking, ease off the throttle and gently accelerate it will go past 3000 RPM but runs rough. And it does not do it all the time.
I have replaced spark plugs, and coil pack.
What else could it be?

 

Have you check the fuel pressure ? low fuel pressure will cause this same problem .

 

Checked fuel pressure, it will be next thing I do.
If I leave the house and drive 3 miles to the store,
It runs bad , when I leave to come back home, it runs perfectly.

 

Some things to look into. Start with the simple and easy things first b/c that's usually the problem:

1) Ohm out temp sensor when engine is cold ...see if it matches outside temp. A bad sensor can spoof the ecm into thinking it's a temp that it really isn't.
2) Check distributor cap contacts underneath, and micro-cracks. Inspect ignition wires and plugs too. A bad plug or coil wire can cause your problem.
3) Prove vacuum - Inspect vacuum lines, for any breaks, cracks or rot. Ensure the front/rear nuts on the intake manifold haven't become loose (common). Ultimately, get and put on a vacuum gauge (you need a gauge) and get the readings. If you don't have good vacuum, it won't idle worth a $hit - ever. And vacuum lines are a constant source of issues with the older jeeps. Throttle body base gasket, etc. Maybe wave around with an unlit propane torch and see if the idle smooths out, which can help source vacuum leaks. But if you don't put a vacuum gauge on it, you'll never be able to prove the vacuum is close to what it should be. A bad valve, for example, which is hard to determine, can screw up the vacuum.
4) Look for carbon build-up in your throttle blade and down in the throttle body. Clean with carb cleaner
5) Remove IAC valve and clean behind it. They often get carboned up. It could be faulty too and that'll screw up the idle.
6) Inspect EGR for proper operation. Remove it and clean the carbon build-up below and the valve on the EGR itself. This is a hidden problem source.
7) MAF sensor. (intake sensor on Renix systems (which you don't have) ...but for the benefit of future readers)
8) You already proved fuel pressure, that's great! -- if none of the other issues above find the source, there's always the possibility of water in the gas, and it acts like fuel and ignition problems. I've chased my tail on issues before only to find out I had gotten a gulp of water from a gas station. Not likely, but keep in the back of yer mind if all else fails.

Go do Cruiser54's tips (do a search).