My 2019 Trail Boss is having these same symptoms. It’s been on and off for the last year but would clear up for several months at a time. In March, it completely lost it and now does this every other time I drive it. It has been in and out of the shop for the past 6 weeks! Chevy Dealership where I live is 3-4 weeks out from being able to diagnose it and you have to leave the truck there the whole time! The only code it’s been saving is a cylinder 4 misfire. They visually inspected the lifters operating correctly. I bought it used with 70k miles and it has the 100k extended power train warranty. I’m traveling to the area where I bought the truck and would like to see if I can convince the dealership to go ahead with lifter replacements. Anyone have any specific verbiage or situations they were able to tell the dealership to get them to move forward with the lifters?
