I have 1996 k1500 5.7 and after the 411 pcm swap the truck idles slightly rougher I?m assuming it?s because the egr is now deleted and it?s block off as well both ends of the tube has been plugged. The problem I?m having the rpm gauge is always fluctuating up and down and I don?t know why. Has anyone else had this problem or have any suggestions?
