I found a red wire under the hood it was taped to a hose that i believe was connected to fuel filter maybe, the other end was loose I dod not know if it was cooected to fuse box or something else but since then my truck has been running rough , It runs good while driving but at a stop or idle it is very shaky, and wants to die. I have put a new muffler ,catalytic, clutch, shocks, brakes all around and a drive shaft, so Im feeling a bit discouraged . I am needing to get a smog done asap and I dont know what else could go wrong . I think that wire has something to do with it, because it didnt start running so ruff. maybe i loosened something while putting driveshaft on I just do not know. Please help