Idle hunts when "warm".

[Mr.Puff]

When I am closer to the second white line than the first white line (a little over halfway between the two) the idle hunts wildly. It is like a rev up to 1,200 then back down to 800 four or five times. The car will then settle back down to 800. What the heck is this?

--John

[rusnak]

we are covering this now in another thread. It is most likely a vacuum leak. The easiest thing to do is get a can of starting fluid, and when the engine is not too warm, spray some around the intake manifold gaskets where the intake runners and engine block meet. Spray some also around the idle control valve and the vacuum hoses. If after you spray, within a few seconds the idle raises significantly, then you have a vacuum leak at that spot. Correct the leak, and try again until the idle is steady.

Mine was leaking at the icv, the little hose in the back of the throttle body going to the ambient air valve, and one of the crankcase breather tubes. When I replaced these, the idle returned to rock steady.

[Mr.Puff]

I suspected a vacuum leak. The idle has been hunting ever since I purchased the car last August (the PO was not very good to her). I replaced the DME, distributor cap, distributor rotor, spark plugs, O2 sensor, and cleaned the ICV. A vacuum leak makes perfect sense. I do not remember this happening before I cleaned the ICV... I'll check that first.

Thanks,

Puff

[scottb]

Check your mixture, too.

[DRACO A5OG]

Puff,

When she hunts, pull the E-Brake and open the lid and use a screwdriver and tape on the ICV. If it settles down, it may be sticking or going out. then check the OHMs.

Jim