What do I need to tune it? Is it something I have to buy, or can you just plug right into my obd port with your tuner and change it? I really dont want to put any money into it as I am thinking about selling it for a daily driven car, like a 3 series or is250 awd or something in that range. I love my truck, but the gas is killer and if I need to haul something I can use my dads new diesel.