High Idle at start up

I know that a car naturally runs a little higher on a cold start up and isn't as smooth...but I have noticed that in the morning, no matter the temp...I will starrt my jeep up and for the first 2-3 seconds its sounds/feels good...then for about 7-10 seconds or untill I put it in reverse and start moving....it feels like I have a cam in the jeep, or the idle is just rough and then as I start moving...it goes away...but it feels and sounds odd at start up.

I recently ran a can of seafoam through the gas tank, the wires, plugs, and cap are less than a year old...I recently cleaned the IAC and TB...down stream 02 sensor was replaced....upstream was checked and was ok...
My entire exhaust minus headers was replaced about 2 months ago.

I have a set of brown dog motor mounts and a new tranny mount coming in that sould be installed this weekend or next week.

Not sure what else to check.

What year Cherokee?

My '94 does the same thing. I don't remember my '85 (carb not injection) ever doing it.

97 4.0

Use the Google, or search the forum, sounds like the check valve has failed, or you have some weepy injectors.

Tim_MN said:

Use the Google, or search the forum, sounds like the check valve has failed, or you have some weepy injectors.

Click to expand...

I really need to redo my injectors, just a lack of money right now...I don't think any of my injectors are leaking, probably just old and in need of replacing...
Also, my jeep has no problems starting...it starts right up everytime, it just runs a bit rough and a little unstable for 5-10 seconds before it calms down.