Mystery Problem???

My Jeep is a 2000, I6, AW4 with 115k (80k on engine)

This happens to me all the time;

Its a warm day (70+) Start the Jeep up, turns over fine, fire right up. Then it will settle into an idle that is very rough. The whole Jeep shakes. Sounds like it has a race cam installed. Very unresponsive and sluggish. I give it a little gas and it is fine. Drives fine, never dies...

So confused :tears:
Searching has been unsuccessful.
This isn't an urgent problem, just seems to be annoying...
Any help would be appreciated
Thanks in advance.

I don't have any help but i hope you find the answer because my '01 is doing the same thing.

So, is the rough idle gone after a couple minutes or after it fully warms up?

This sounds like the IAC but we need more info.

Does this happen starting from cold or after a run and short stop. My XJ have this happen very often when it is restarted and the engine is hot. It is called heat soak. Maybe the two are not related. Give us more information.

This only happens after i run it, then turn it off, let it sit for no more than 15-20 minutes, then restart it. If I cold start, she purrrs like a kitty.

To answer Joes Question; the rough idle seems to go away after i give a few seconds of 2.5k+ throttle. I havn't let it sit fore more than a minute without touching it to see what would happen.

EDIT:
After googling "heat soak jeep" I have found this;
http://jeepin.net/forum/showthread.php?p=975138

This seems to be dead on all of my symptoms. To sum this article up, injector #3 heats up after turning off the engine, the fuel inside it then vaporises. Then when you start the Jeep, cylinder #3 misfires, causing rough idle. The engine then will run fine as new, cooler fuel, is pushed through the injector returning #3 to working condition.
Pretty much the cure is to wrap your injector in heat shielding material, which i will be doing tommarow.

Thanks to all who replied, especially Techno.

I did not know that article exsis but it/you is accurate. My '96 have been doing that as long as I have it especially in Miami. I know what the problem is so I do not worry about it, I just release the pedal for a bit then press it again. My ,94 that have a return line from the injectors to the tank never do that.

Insulating the injector does not always help. The most complete cure seems to be a timed switch on the efan to keep blowing air over the engine/injectors for a few minutes after shut down. Search the heat soak issue more and you'll also find that information.

winterbeater said:

Insulating the injector does not always help. The most complete cure seems to be a timed switch on the efan to keep blowing air over the engine/injectors for a few minutes after shut down. Search the heat soak issue more and you'll also find that information.

Click to expand...

x2. Here is a link for a timer, the ELK-960 would be the ticket: http://www.at-fairfax.com/ConstructionElectronics/RelayBoardDelayTimers.htm

Well i just finished wrapping the injector and fuel rail in insulating material. I will keep you guys updated on if it works.
If it doesnt, the timed switch seems to be a good idea...