My '87 Mustang is idling really high right now. It actually just started tonight. I only owned the car for about 3 weeks now and this is the first night I got to really drive it (more than an hour of so). I was cruzing around with friends of mine. When I came to a stop tonight and pressed the clutch in, it idled at about 2000 RMPs. Then, when I went to park at my house, it idled at about 1500 RPMs. What could this be? Idler control? As far as mods, I have none except MAC Catback right now.