Just aquired a 99 Legacy, my first Subaru while looking under the dash for the fuse panel I noticed a single wire above the gas pedal that has a green plug on both ends. This wire is unplugged , seperating the wire. I conected the plug and started the car, the check engine light flashed continuously. So I unplugged the wire. My Q is, should this wire be left un plugged or is it normally conected?