I failed emissions because I am running a 3.5 HO on a 2002 2.7 PCM. It is an EGR thing. I want to replace it with a 3.5 PCM. I understand that I need an 03 or newer because my 3.5 motor doesn't have EGR. The place I get used parts from doesn't keep the keys to their cars and they don't know what they have in the yard. They do have cars with 3.5 HOs though. So here are the questions. How can I tell, without the key, if the car has SKIM? Do I need to replace anything else with the PCM if it is not SKIM? Finally does anyone have a PCM they want to sell?