I just Replaced my Cylinder head for the first time. I replaced all the gaskets and spark plugs and wires distributor cap and rotor. I started it back up today for the first time and it revs up uncontrollably. I have to turn it off. What have I done now?
1997 jeep cherokee sport 4.0 in 6 cylinder

 

check all vacuum lines, did you remove fuel injectors?, Idle Air Control? sound like you have a major vaccuum leak. Spray Carb cleaner along intake throttle body, itll bog down when/ if you find vaccuum leak no leak check tps IAC make sure they are connected

 

Subs. I'm about to change my head so i'm looking to see how this turns up incase I run into the same problem

 

its gunna be ur iac, i did my head and thats exactly what happened to mine, at autozone mine was 29 bucks

 

I will look at that and get back.
I replaced the fuel injector gaskets, water pump, thermostat, cylinder head, manifold gaskets, i never removed the throttle body.

 

Vacuum leak or intake gasket leak are generally to blame for this type of problem.

 

like stated get gum cutter and spray all the Injectors on the intake side...try to get the intake where it meets the head also.....Try unplugging your IAC

 

I replaced the IAC and throttle body gasket to no avail. The engine wants to fly out of the jeep.

 

did you at any time remove your throttle position sensor? If you did then maybe you reinstalled it wrong, like if you put it in and turned it, it could be reading a false throttle input.

But if you never removed the TPS then disregard.

 

still a TPS isnt gonna cause a motor to rev out of controll...it doesnt open the throttle body. The engine needs air to rev..which it is getting from some where.

 

Check the throttle cable, make shure its not in a bind. Check to see if the throttle body butterfly is seated at the closed position at idle.

 

If the throttle body is closed, and in good shape. I would think the way you describe this is there is a leak at the manifold-head. Check that and make sure it is ok, they can be tricky sometimes.

 

I have removed the intake and exhaust manifolds again and i am going to reinstall.

 

your intake/exhaust manifold bolts might not be tight enough. It they are not tight enought it will rev up and down by it self. Let us know

 

check your vac line to the brake booster.....