Got back from a week out of town, started the car, and it idled very high, sometimes above 2000rpms. After a bit of this, it threw a CEL, which I pulled as P1507. After throwing the CEL, it runs like crap; I guess that's the "fail-safe mode" that the CEL refers to.
I researched that out, and educated myself about the Idle Air Control Valve. Pulled it off, cleaned it up with q-tips, (per Nasioc instructions), let it dry overnight, cleared the CEL, and put it on to test. Same result.
So I'm going to pull it back off tonight and clean it with carb cleaner, and try again, but I'm starting to wonder if I'm missing something. I checked for loose vacuum lines; didn't find anything. I have a 5MT, so the references that I've seen to a "neutral switch" don't apply. Another fellow on here has said that changing a thermostat fixed his...but I don't see how this is relevant when I've just started the car cold.
Any other thoughts? If this doesn't fix the issue I'm looking at shelling out a couple hundred bucks for a new IACV. Before doing that, I wanted to investigate all cheaper options.
Thanks for any input!