Showing code p0660 what does that mean

Unfortunately, you have two options: throw parts at it and cross your fingers, or take it to a professional with the proper scan equipment, and get a proven diagnosis. The code means your intake manifold is not tuning to changing conditions properly. This can be a result of the AIS solenoid, the manifold itself, the PCM or just bad wiring. It really needs good hands on it to diagnose. http://repairpal.com/mitsubishi-within-10-miles-of-mannington-west-virginia-26582