2RZ high Idle.

So I just finished rebuilding the top end of my truck; for reference here's what I did to it.

Head professionally machined.
New Water pump and Fan clutch
Radiator hoses changed
New Timing Chain
New Oil Pump
New Air Filter
New Spark plug wires and plugs
Distributor cap and Rotor
Thermostat
Cleaned Injectors and intake manifold
Center force clutch kit and Luk flywheel
New gaskets for everything
ALL fluids drained and changed

So I put it back together and it fired right up; no check engine light, all vacuum hoses reconnected, but my idle is around 1500rpm in neutral as well as in gear. The airconditioner seems to make no difference.

Any ideas? would it be acceptable to just adjust the throttle cable?

 

you have you vacuum lines mixed up and the fast idle is on for cold startups. also that may need adjustment since it should fast idle around 1200 rpm and warm idle is 650 rpm

before going into the vacuum lines just confirm the throttle linkage isn't the issue by disconnecting the cables to it. maybe it or the cruise control cable is stretched and pulling on it.

 

No! The idle normally is controlled by the IAC. Something is not correct, so find the problem and fix it that way.

Either the computer is opening the IAC valve causing the high idle, or the throttle is open more than it should be, or you have some air leak somewhere else.

See if you can manually close the throttle more to make the idle go down. If so, then see if the throttle opener (diaphragm thing) is holding the throttle open. Possibly the vacuum line got damaged or clogged during the rebuild.

The throttle plate has a stop screw which should be set to just contact the stop lever when the throttle plate is completely closed. You shouldn't have to adjust this, unless you changed it for some reason.

 

okay, I'll look into the vacuum system first. is there any way I can get one of you guys to take me a few pictures of how your hoses are connected for refrence. I plan on replacing a few of the hoses anyways and that would be helpful. I never actually did anything to the throttle body itself; however, I remove and put back on the linkage (which is held in place by two nuts) I was just wondering if it may be possible to have accidently tightened the linkage that way.

 

Just went through the high idle a month ago myself. I had to take apart the IAC valve, clean and replace the dealer only gasket. that did the trick. However I did this after cleaning the MAF and making sure the vac lines were OK. It was a pain, but only took an hour or so to clean the IAC valve after all was said and done. After a top end redo like you've done, this starts to get pretty easy.

 

There shouldn't be any tension in the throttle cable. It should be just loose enough to allow the throttle to fully close. So, you may have installed it with tension if you turned both nuts.

This is the best picture I have showing the vacuum lines on top before disassembly. Two of the hoses in the picture go under the throttle body to the VSV for the EGR. The VSV doesn't allow vacuum to the EGR valve when the engine is still cold. You may still have a vacuum hose diagram sticker on the underside of the hood.

 

It looks like all of my lines are connected correctly and most of the hoses are still in good shape. I'll replace a couple of them and move to the Idle Control Valve.