Idle problem

Ok my car starts up fine, but it idles very high. I hit the gas and then it sounds normal but idles up and down, up and down but never smoothes out. I have tried adjusting the idle (screw) but either it idles high or up & down? What should I do. I just got my head fixed and put on, so should it be like this for awhile? Will it stop?

my car does that too, but after its warmed up it stops.

3 things (4 if you've bent the idle screw).

#1 Check the vacume hoses to your manifold (unlikely).

#2 Fast Idle Valve will need replacing (located on the block).

#3 Get a new/second hand throttle body with the Throttle Position Sensor UNTOUCHED, as in having the original sealed screws in it. Do NOT buy it if it's been tampered with or reset.

Reset the ECU and drive away happy :)

It always seems to be these things

Cheers