87 xj 4.0 It doesn't happen all the time. Doesn't matter if it's cold or warm. Sometimes when I start it it'll rev up to 4k-5k and stay for a min or two before it settles down. It drives fine. Throttle responses normal. Any ideas? Tps? Iac? Intake gasket?

 

Yea I have some ideas but no one ever wants to hear them...... any ways back on topic do Cruisers tips, you will need to do these before you do anything else, otherwise you are just throwing money away like I did. Chances are you will fix your problem with little to no money. DON'T SKIP any of the ground refreshing tips either, don't just look at them, actually take them apart and clean them.

https://www.cherokeeforum.com/f51/cruiser54s-mostly-renix-tips-153657/

 

See post 2. Do Tips 1 through 5 with no shortcuts.

Post 27 is becoming one of my favorites over post 2......

With the engine cold, check to see if your intake manifold bolts have loosened up.

How high an idle, and does it come down without having to turn the Jeep off and restart?

 

Idle is about 4k-5k and it will calm down after a minute without Turning off.

 

4000 to 5000 RPM?

That's not good!!!

 

Yeah. It's a 5 speed. So I put it in gear and with my foot on the brake I let out the clutch a little to keep the rpms down until it wants to behave.

 

Start with what i posted above in #3..