Originally Posted by HeyYou

That, I am not entirely sure. I don't know if the PCM will also stop injecting fuel/firing the coils on the cylinders it thinks should be deactivated..... Likely it doesn't.... which means you will have four dead cylinders, that are still doing the compression thing. That will REALLY turn the truck into a dog.

Originally Posted by hookinhogs

It has a CEL so the MDS system doesn’t work. I have no fear it’ll turn on or work in that way, my fear is for some reason it changes the fuel or timing because of the lack of the MDS system and that damages my motor that way.