Ok so ive been having alot of issues with my gt recently, she was running really good after i swapped my upper plenum for a ported and polished crown vic plenum. Then after about 100 miles of driving it started running really rough and threw codes for lean bank 1 and 2, insufficient egr flow, and it felt like a misfire..... i remember reading a thread a while back and after the guys plenum swap his iacv went bad, and a few others had the same issue. Could that be plausible for this situation? Replaced plug wires, swapped around injectors, new dpfe, new lower manifold, new screamin demon coil packs, im stuck. When pulling plug wires 1,2, and 6 off the coil pack theres no change in idle and it runs really rough. Any help would be greatly appreciated. Oh and car is a 97 auto gt with 144k miles