VAFC problem

hmmmm

sound slike it is not installed correctly, otherwise the vafc with it default settings (installed correctly) should not affect anything.

Have you checked apex'i site to see there was not an update for your car , as there have been many changes to the original documentation due to incorrect pins being specified.

Hey I just installed mine, the part you are talking about confused me some also, the self learning of the throttle, you are suppose to set this while on the screen that has the cyclinder number and the up arrow, I did just as it told me but nothing happened, I assumed it just would get a "feel" for the throttle, and display something but it didn't, check your sensor chk, the thing that displays voltage of throttle, prs and rev's I believe, your throttle should go up to about 4.59(voltage measurement) or so but my car is an 00 SI, I'm not sure if it would differ. I went on through on the settings cranked it up and everything worked great!

Read about the VTM wire, they added that to newer manuals because it seemed to resolve problems with the engine.