My SW1 is a great car, but it recently started to stutter under light acceleration, and it get more noticeable the faster i am going. i discovered later that some of my spark plugs were arcing on the engine block, so i replaced the plugs and cable, which fixed that, but not the stutters. now i asked my dad what he thought and he said it could be the EGR Valve, so i unplugged my EGR and the car runs great, unfortunatly, i get terrible gas milage now (17 MPG) i actually started getting that milage when the problem started. now my question is is the EGR valve toast and i need to get a new one? or can it be fixed?