High idle all of a sudden?

I start my car and come inside the house while its warming up. I hear it getting very loud after a couple min. I go out and its idling steady at 2500( usually it idle's in park at like 800ish). Put it in Drive and it smacks pretty good..drive it home fine with no problems and even was fine when i put it in Park at stop lights. I guess I'll see if it does it tomorrow morning during the warm up before class. WTF could it be? The lady put "regular" gas in it the other day by accident(crappy 87 oct.) when I told her Plus. Would that affect it b/c I think I noticed the exhaust louder since she gave me the wrong gas too. Thanks for any help or advice.

It's completely common for our cars to have a high idle war warming up, it warms up faster this way. That being said, 2500 is still kind of high, if it continues to do this, try adjust the BISS screw while it's doing this, or look into the ISC motor going bad.

It's completely common for our cars to have a high idle war warming up, it warms up faster this way. That being said, 2500 is still kind of high, if it continues to do this, try adjust the BISS screw while it's doing this, or look into the ISC motor going bad.

I warmed in it up twice today and no problems. Real weird... anyways..if something happens or I notice anything weird,ill post back. Thanks

no problem

It hasn't done it since and I warm it up basically everytime I drive unless it is warm. I'm hoping it was fluke... but that would be too lucky. Time will tell..