If the IAC valve was bad would it cause a loping idle until the car is up to running temperature. Because I start the car, it idles at like 2000 for a few seconds, then begins to lope between 1000 and 2000, and once the car is hot and at the temperature it runs at it idles normal at about 800. I don't understand what would cause the problem to only happen when the cars cold. It's a 90' Accord DX.

 

when the engine is warmed up and at a steady idle, unplug the IAC and the RPM should drop a couple hundred. So simple a test; a caveman can do it. LOL
I would think the FITV might need adjusted allowing the engine is full of coolant and the block burped of air thru the 12mm bleed screw at the T-stat housing.

 

Well I have unplugged the IAC and it still lopes just sounds like it is going to die and theres less of a RPM difference during the loping. I've bled the coolant, I've cleaned the IAC, I've cleaned the FITV, but I can't get those 2 damn screws off the top. I'm not sure why Honda would use philips head screws on it, but they're stuck and stripped pretty bad at this point. So once I do get those off though, there is a way to adjust it? What do you have to do to it to adjust it?

 

My car used to do that when I would start the car cold and then shift to R then back to P or N. It might be a similar problem that isn't as bad but what actually solved it is running seafoam through my car. I didn't do it to solve the problem, but I thought I'd clean out my engine with a 1/4 of a can before I did an oil change. If you do what I did make sure you change your oil afterwords. I ran seafoam through the brake booster line. As long as your car burns a very small amount of oil and the engine is in good shape, I'd recommend doing it.
I'm not sure how it helped since it probably didnt run through many of the idle control components, but it did work.

 

Well I adjusted the FITV, and it idles absolutely perfect. You need to change it a little to get it exactly where the car wants it, but it idles great now. The only trouble I had was getting those 2 philips screws off the top.