start with baisic tune up... see you did your wires but did you do your plugs... read the plugs see what each hole tells you. i X2 4thgen but get a scanner and look at the tps% if the engine is not running you should see a steady increase of % as you press the pedal. if it jumps around then it is bad... but they are kinda pricy so that is why i say start with the cheep parts if you are going to do a "throw a part at it and see if it fixes it"