Complete engine problem

I have a 2000 grand am 3400 v6 auto. Car idled high and would skip now and again. Blew out cat converter, wasnt it. Had intake manifold gasket replace, got it back acted up even worse and had to get the head gaskets replaced a few weeks later. After finally getting it back, it still skiped but now when I step on it, it sounds like a machine gun as I would explain the noise. Fuel regulator diaphram was leaking, replaced it along with the alternator. Now it will make that noise all the time and I know that its not a good thing. Things ive done to the car are, subwoofers a racing exhaust, and I also put a ram air kit on it. Could it have anything to do with that or is my problem even deeper than I think. Ive been told no back pressure would screw with it, and also that my anti theft could be shutting down my fuel regulator. Im getting sick of puttin money into the car on things that dont help. What usefull advise would u have to give, im outa ideas