97 328i has racing rough idle, I'm at a loss
I recently bought a 1997 328i convertible for my wife, it had a rough idle so I replaced the idle air control valve, the hose to it, valve cover gasket, and the spark plugs. Now when you start it, it races up to 3000 RPM, then comes down to a rough idle. After driving it, it races at a stop while in gear and makes it almost impossible to stop and when I got home, put it in park, it almost redlined the tach, I had to shut it off! When I re-started it, it raced up there again? Any ideas? I am very mechanically inclined but I don't have much experience with BMW's and I'm at a loss right now. Any help would be greatly appreciated.