2003 Ford Windstar abnormally fast idling when cold

Thanks for responding.
Let me be clear. When its cold, if I give it gas, it appears to take its time coming back down. If fully warm, it comes down faster, but maybe a slight laziness.

When I start when cold, it'll idle high, like 1600rpm, and for first ten minutes or so of driving, it'll go itself, itll get to 20mph and even shift into second, without me giving it any gas whatsoever. Unless the engine is very warm, say, after 30 minutes of driving, itll seem to want to idle around 1100rpm, or maybe sometimes 900. Only unless I'm driving for long period of time does it get to 750rpm.

And, especially when cold, when I am travelling with velocity, and have to brake ahead, it'll seem like theres a poor mans cruise control on, it seems to coast forever, and I'm constantly holding the brake and way too early, for any braking ahead. It is much more dramatic when cold.

I changed the PCV grommet, changed the throttle sensor, cleaned the IAC valve and throttle, and cables.

I have no engine codes at all. I did have one when I changed the TPS sensor.

I shook the PCV valve, it makes noise.

I checked all vacuum lines in front of engine and did the best I could checking the lines in the back of the intake without removing the cowl.

Someone said something about checking the EGR valve, and I did not yet, for I don't know how.

Now what do you think?

You know something, it feels like when I drive, im using the brake more than the accelerator. And I have one of those electronically adjustable pedals, maybe somewhere between the pedal and the throttle is sticking, but I don't think so.

Another thing is that the prior owner has one of those remote starts installed, I wonder if that is what is messing things up.

Im not getting any codes, however, I keep thinking I have that isolator bolt problem.

Well if the IAC valve/motor is bad, shouldn't it trip some sort of error code, maybe like "too lean" or something? Im getting no error codes.

The IAC valve is completely clean, though not fully seated/closed when disconnected, but I think thats normal. But get this. When cold, I started engine, it revved high initially like 1900 and within ten seconds of starting, I disconnected the IAC valve, and the rpms dropped to 600, and then after a minute or so the engine finally died. Does this mean I have a vacuum leak, since the engine continued to run with the IAC valve disconnected, though only for a minute? And if yes, do I need to remove the cowling to check the rear vacuum lines or can they be checked when on a lift?