hey guys i bought an s5 with a TII conversion. i replaced the fuel filter, plugs, oil and air filter and the car while it is cold will crank right up and die. now if i hold the car at about 2500rpm to warm it up for about one minute it is fine after that, with the exception it will stumble under hard acceleration for a while. but after a few minutes of driving the stumbling goes away and as long as the car is warm it will idle fine. i know the engine is ported so it has a lumpy idle but it is also kind of rough. also the acv is blocked off so maybe that could be it? or does it sound like a vaccuum leak? i already checked for air leaks in the intake and intercooler piping and nothing was there.