So i'm somewhat decent with the electronics aspect in cars, but the engine has always been a foreign concept to me. I'm around 51K miles now and looking to do a tuneup. I dont want to go to a shop empty handed and just have them do a tune up with generic parts. I am willing to invest some money in parts if they are good quality that will ultimately pay off either by better gas mileage, longer engine life, or better performance (stock 1.4L engine). I just want to keep my baby as young as possible for as long as possible. Does anyone have any recommendations for parts?