Hey guys, when I start my car, it revs at about 2 k for about 30 seconds and then slowly comes back down to about 1000, and if im lucky down to about 800. What could this be? It started about 2 weeks ago when i got my oil changed/check up at the dealer.

 

Sounds like they played with your IAC while they were 'checking' your car out.

 

Something else to look at would be any vacuum hoses they may have unhooked. With the hood open idling in neutral can you hear a sucking noise from anywhere? If so follow the sound. Then look for unhooked or broken hoses.