2004 Ford Crown Victoria Idle

The car has an idling down problem when warmed up. Normal cold start idle about 1500 or so rpm and drops down gradually cause it is of course a cold start. Let's say I drive it and it gets up to operating temperature and I go into a store and come back out and start it.A normal car would start and almost instantly drop to idle (Atleast all cars I've driven even of the same model)but my car I come back out 2 min later fire it up and it'll sit and idle at let's say 1100 or so rpm for about 20-30 seconds before going to idle even when warmed up.I've cleaned the throttle body. The iac the maf sensor idk what the deal is with the car why it takes forever to drop to idle