This is my first forum post ever. However i do have automotive experience, i have worked as a tech for 7 years all of those years working on german cars. To the point, i own a 2004 Grand Prix 3.8 series III NA, i have owned it for almost 9 years, i purchased it with roughly 150,000 miles on it, it currently has 277,500 miles on it and is running strong, interested to know how many miles some other have. This vehicle is my daily and only vehicle i have done nothing major to it and had few problems, i have done the typical upper and lower intakes and very very regular maintenance. Most recently have replaced the entire steering system due to leaks. i currently with only putting a hundred dollars or so every few months have gotten the entire engine bay sealed and leak free, yay me, only items left on my list is rear suspension and struts/springs all the way around(will be looking into this later). To note everything on this vehicle aside from rims is stock. Love this car due to its reliability, will drive it till it dies, rebuild and do again, joking(kind-of). I have ran into a problem and seemed to have exhausted all my options aside from pcm error or engine not creating enough vacuum, only fault code on is P0401(egr insufficient flow), have no vacuum leaks(verified by using a smoke machine) i have checked all wiring going to and from the pcm to the egr, replaced the egr valve, removed intake to check for issues, none found. checked the intake side and the exhaust side of the egr, both free of any carbon. vehicle runs and drives very good. Aside from removing lower intake gaskets and re sealing just to be sure (recently done aprox 60k miles ago), pcm being bad im not really sure where to go any more. i have freeze frame data i can post tomorrow. Next thing on my list of things to do is check running vacuum. just have to find time at work
