idle fluctuation when first starting up

this is probably a stupid question, but:

when i first start my car, drive it out of the parkin' lot at work, then hit the red light (crossing, not hookers), my car's idle (rpm) dives down, jumps up (not too much just to 1400 or so), and fluctuates a bit, is this totally normal, and is it just the computer finding the best air/fuel ratio, and does the fact that my AIR line is disconnected from the air intake affect this at all

thanks for the help
ian

Possibly with the line disconnected. Have you tried plugging it back in? See if still does it.

IAC (idle air controller) should be the problem...try cleaning it...or if you dont feel like it just get one at murrays...there 29.99...had the same problem with my car