Gkistler

Hi friends - first time poster. I have a 2015 sierra Denali with 150k miles, I’m the second owner and she’s given me 75k of great service. I run a pulse AFM disable device. Starting Thursday when I exited the freeway after a short local ride it started idling rough, with an obvious misfire shake and was down on low end power. I got it home and hooked it up to my scannner and found no codes but in live data a pretty bad misfire on cylinder 5. I replaced the coil, plug and wire with all new OE replacements (Delphi gn10165 coil, acdelco wire and 41-168 plug). It’s still behaving the same way after firing the parts cannon at it. I know cyl 5 is a non AFM cylinder so I am not thinking this is AFM related but I’m kinda at a loss. injector? Bent pushrod? It’s running too well over 1k rpm to suggest those IMO. Has anyone chase this issue before and what was it? Any suggestions?