aight guys im posting this for a friend...
said his car revs between 1k and 2k at idle...we check all the vaccuum lines...smoke tested everything, changed out map sensors check all grounds and radiator coolant levels but theres nothing else i can think of to get it to stop...anyone having this problem and know how to fix it?

 

Check under you throttle body (Fast Idle Valve)
Take ur throttle body off, under it at the end it should be a gold-copper end cap, open that end cap and screw down the plastic hosuing. Close it back up and your problem should go away....

 

What year and model?

Have you cleaned out the Idle Air Control Valve screen?

 

its a 94 4 door sohc vtec motor...yeah thats one of the first things i tried becasue my car used to have the same problem and after cleaing the IACV it was fine. we did that on my friends car when it happend the first time and it fixed it but now it must be something else...ill try out the fast idle thing...

if you got any other suggestions please shoot. thanx

 

Fast idle....It acts horrible in the morning. Then after it warms up. it calms down.
ECV. It does it all the time.........check your PCV valve.

There is a secret to fixing the fast idle. Once you take the throttle body off. Take off the fast idle.

After it's taken off. Shake it to see if it rattles. If it rattles then you have no luck you must buy a new one. If it doesnt rattle. Take off the end that the coolant does not enter. The back side.

Open it up. Spray some Wd-40 to lubricate for the next step.
Get a flat head and slowly tighten the vavle back down carefully. Sometimes they losen becuase of viberation from the motor.

After it is tightened back down, get a little honda bond and rub it on the valve and the valve wall. So it doesn't back out again.

Put it all back together and it should work fine.
Hpe that made since.