It starts at a normal level, around 1000-1200, but drops about 100 each cycle until it's around 300-400. Then it "stabilizes" at 300, dropping below it every couple cycles, then revving up to 450 for a cycle or two. The RPMs are alright while driving, but there's a lot more engine vibration and if I don't bring them down slow enough the engine dies completely.

The map line was unhooked for a couple 20 minute test drives while I was trying to diagnose the rough engine. The line had come loose and fallen behind some other hoses so I didn't know it wasn't hooked up until I was pointed in that direction on here.