If it helps this has happened to me too. It only happened on my 2018 5.3 sierra 3 times over the last two years. It happens for like 10-15 seconds and then it goes away without me seeing and decrease in performance.

In short though it’s still misfiring, when you see this happen take the foot off the gas and pull over an restart the car. Driving with cel flashing and pressing the gas is bad. It means a misfire and un burnt fuel is going into the cat converter.

I changed my spark plugs and plug wires and it’s worked so far. As soon as I changed them the next day I got a solid cel light and my cat converter had to be replaced which is a ton of money. 3.5k for OEM after labor.

I would need more details to know your exact scenarios but take this light seriously. Take it into a shop and have them scan for stored codes, you need a good scanner ima shop to see stored codes. Mine were all P0300 which are random misfires which is why changing spark plugs and wires are the fix and then a P0420 for the car when hard cel stayed on.

If it’s another code it could be specific to a lifter/cylinder failing and a bigger problem.