Ok I have had the same problem as many others I have seen here and on other sites. When accelerating, I would get a blinking CEL and the service traction and stability control message would come across radio screen. Sometimes would even get engine in low power mode. Ran the codes and kept getting misfire on cylinder 3. After reading extensively on this issue in many places where GM mechanics couldn't even explain after replacing all plugs and coils etc.
Well.... I cannot take credit for this as I believe I read here somewhere of this very simple cheap solution. I would give credit to who originally posted this but I cannot find the post again. I apologize..
Ok so here goes. Instead of replacing all plugs and coils,as my plugs looked fine and a bad coil is very unusual, I did not replace. But... I did remove all coil packs and plugs. I inspected to make sure there was no visible damage. And I wanted to try this without any new parts just to see if this was the issue. I cleaned everything up. I then applied dielectric grease to all the coil pack wire connections. Then I also put dielectric grease inside the boot that goes over the plugs. I put all plugs and coil packs back in. I also cleaned up the mount surfaces on the coil packs and greased those to where they mount to engine. I did not clear computer. Started car. gave it a few revs. Then decided lets test this out. Drove. Drove pretty hard. No misfire, no stutter and no traction or stability service messages. But... Still had solid CEL light on. So I parked it. And drove 2 more times. Car ran like a champ. On third drive, CEl light went out on its own. Car runs like brand new. If you are having this issue, give this a try. I had mechanics and read all kinds of crazy solutions. This is only solution that has worked. Even if you replace coils and plugs, liberally apply dielectric grease to all points mentioned above. These cars have extreme electronics in them. One of the GM recalls fixes is actually applying dielectric grease to the computer pins. Alot of these electric problems with these cars is just corroded or bad electric connections.
I hope this helps some folks out there having these same issues. It helped me and now my G6 GXP Street Edition runs like the car it was designed to be. Very happy. Thank you for the original poster.
Happy Driving.