Bouncing revs?

[The G-Man]

I noticed tonight that after I press in the clutch and put it in neutral to like prepare for a turn that the revs go down to about 1000 and then bounce back up to about 1500, and then slowly go back down to 1000 where the idle is now.

I just had the clutch replaced by a mechanic. I have not yet tinkered with the idle adjust screw either.

[NAiL05]

Hows your coolant level? Somtimes that will cause a minor fluctuating in the RPM. You try cleaning the IAC/ adjusting FITV?

[The G-Man]

I cleaned the IAC valve like 2 weeks ago. Not completely postive on my coolant level. But like I said, this only happens when I take it out of gear and I am slowing to a stop. It then regulates itself and goes back to correct idle.

I will try bleeding the coolant, since I have not in a while, and defiantely not since I cleaned the IAC valve. But this has just arisen in the past 2 days.

[mozzandherb]

I had a bouncing idle and today I replaced the IAC valve because I thought that was the problem, but it wasn't. There's another valve right below the throttle body and the problem with mine was that the threaded piece that controls temp and coolant was loose it just fell right out of the valve cavity. So we tightened the screw and voila my idle was o.k. My idle was really bad though, boucing from 1000-3000 while I was stopped or slowing down. Anyway check that other valve you might have the same problem.

[The G-Man]

I think most definately this is a coolant problem. I just got the car in March, and never really drove in freezing temperatures. When I have noticed the problem most it has been in the mid 30s F. I think if I bleed the coolant it will be fine.