2000 V8 RPMs Up and Down

[JEEPGRL]

am new to this board and am in need of all of your expert opinions. For a couple of months my 2000 Grand Cheroke will idle up and down while in park or stopped in drive between 1000 and 2000 rpm. This past week, it has become more frequent and is now doing it at speeds of 55 mph (going between 2000 and 3000) and sometimes is feeling as though it is neutral. It has also died twice, it just dropped so low while stopped. It is shifting hard from park to reverse - jerking, which I have attributed to the rpms being too high. I have noticed if I "gun it" while it is doing this, either in park or drive, the problem seems to temporarily stop. Any ideas of what it could be would be greatly appreciated!

[Cam7]

Does your Check Egine Light come on? Part of the problem sounds like your IAC motor when it stalls. The hunting could also be IAC related also a dirty throttle body, pcv, weak fuel pump and vacum leak. Check the Iac motor if its carboned up give it a good cleaning along with the throttle body using carb cleaner and a tooth brush. If check engine light is on try to get codes and post back.

[JEEPGRL]

The check engine light has not come on - and when I flip the ignition 3 times in a row, all clear - no codes. I will try what you suggest, but I am wondering if maybe it is a sensor problem and if so, which one.

[Cam7]

Usally a sensor problem will throw a code although some dont always throw one. A Coolant temp sensor will sometimes act like that, also a Throttle position Sensor. its hard to tell without a Scan Tool. A vacum leak is a another place to check. Hope this Helps.