Check engine light flashing

Don't drive it with a flashing CEL. More than likely you have a coil that has gone out. Getting the code will help you identify which cylinder it is. When you know which cylinder it is, swap the coil with another coil and see if the code follows to the other cylinder. That will tell you the coil is bad. Also, for the stalling, cleaning your throttle body is first step. Due to our platform not having a traditional pcv valve, our throttle bodies gunk up. Should clean it at min. once a year.

Thank you!!!! I did not drive it. Got a code reader and it had a 301 code. Switched coil 1 and 2 to see if code would follow n got a 300 code instead??? Now I'm confused. I was hoping it would follow or at least pull a 301 and 302 so I would know it was spark plug and coil pack. How should I diagnose now???

First things first, make triple sure your coils are seated correctly on top of the plugs. Very easy to make an error here. Remove it, reinstall, listen and feel for the click. Did you check your plugs? Should only use AC Delco 41-103, this engine loves these, other brands have documented problems with our engine. I'm still leaning towards one coil being bad here. Engine running, try disconnecting (just the wiring to coil, don't remove coil itself). If engine runs worse, that coil is good. If you notice no difference, likely that's your bad coil. Clean your throttle body regardless. Remove fuses #10 and #28 under the hood, then remove the throttle body (4 bolts +wiring connectors) and clean with a sensor safe spray like Seafoam, a toothbrush, and a rag, both sides.