Had to walk away from the GN again. 99% of my problem is I don't have a scan master so I'm limited in diagnostic technology . I Have a code reader and am getting an occasional 44 lean code that is driving me nuts. Ive checked everything, TPS values, no vac leaks, new plugs, new wires,new ISC, new egr, new O2 sensor, all checks outs car drives and runs quite well but idles like . The only thing left I can think of is could this insanity be caused by a crack in the driver side header? I'm ready to give up and send this car down the road or admit failure and let cotton work his magic on it .