6.4 will sputter & shudder & smoke white about 3/4 of the time if you let it sit and idle for 2-10 min. Showed #2 cyl code so replaced that inj. Didn't show other codes till now a p0488 egr code. All you need to do is either restart truck or reset diag codes while its running and it will run like a top again. the cyl 2 code comes on again after it acts up. and the egr one comes right back on even if it runs fine. Can the egr throw a cyl 2 code and then work perfect with just a clearing of codes or restarting?