6.0 powerstroke issues

Hey guys. I have an 03 6.0 that is super weak cold. Is not skipping. Everything i have checked appears to check good. Have replaced egr valve, icp, hpop, #7 injector for a skip. Any ideas.

And one more question. I just changed my thermostats out and everything, after cutting my pinky to the muscle on one of them, and the check engine light is still on. How would i reset it or make sure that they are working? I put them in to my best of knowledge. They weren't the same top as the stock ones.

So is there a way to reset the light or should I just drive it?

It was never over heating in the first place. The light came on and the shop said thermostat codes and so did you guys.

Thanks!

Ford 6.0 diesel ? prone to EGR problems that cause overheating that evolve into head gasket problems. CPU was very trouble prone also. lots vids on youtube about 6.0 and 6.4. The emissions was experimental and Ford and Naviaser split was over the problems. Most remove or bypass EGR system