The deep freeze seems to be bringing all sorts of issues out of my truck (94 pickup 4x4, 22re)...as always:) Here's one I'd like to solve: I've got an idle that's always wanting to rev up. Stepping on the brake pedal seems to bring it down (sometimes), but it always and almost immediately revs back up to 2000+ rpms. The only way I can get the idle back down is to engage the clutch in a higher gear. Once it's down at or below 1000 rpms, it usually stays there.

I've heard this could be a dirty throttle body, fuel injector, or a vaccum leak. Well, I've run several cleaners through the system and had no effect, so I'm guessing it's a vaccum leak. Are there likely or more common spots I should check first, and how do I really go about finding the leak? Or, if this doesn't sound like a vaccum leak, what else could be the issue?

Thanks!