So I've been chasing for a long time a slightly rough idle that's throwing no codes. 2011 Sierra 1500 5.3 190k miles. I was checking spark and the spark defineley skips randomly. however it does it on every single one. I have a hard time believing that all 8 coils are going bad and doing the same thing. I will upload a video of the best shot of the spark, just keep in mind each coil is acting the exact same. So y'all think all 8 could be going bad or something else could be going on?