Idle problem

I have a 93 LX 5.0 and last night I took my cold air off to do some cleaning. Today, going to and coming from work, it was idling at 1500 to 2000. Any ideas as to what I may have bumped or if some of the components are just wore out. Has almost 150K on it but still runs like a scalded dog.

Thanks for any help anyone may be able to give.