I'm having a somewhat odd issue and wondered if I can post it here and get some thoughts. If not, I guess delete post and I will find the sub that is allowed in.
This is a 2011 Silverado LS 5.3L, my issue is an intermittent misfire code p0304, which is the 4th cylinder misfiring. It happens seemingly randomly, and seems to ONLY happen after I have driven some distance at 60+ mph and then slow down to stop. The cylinder stops firing and gives me a code. After a few moments usually while driving it will even out and the code goes away. I have changed spark plugs, wires, and tested the coil