Need some help !!!!!!!!!!!!!!!!!!!!!!!!!

I think I went into a panic when I saw the black residue, since I have so many issues trying to get this thing sorted out. It is not oil, it is some sort of black residue. I don't see it in the radiator. No overflow tank. I will get a picture of the spark plugs also. I will try and get one of a cylinder and maybe some video of it idling. When I posted about the cap jumping up from pressure the engine wasn't exactly ice cold. Later after I posted that I went back out and touched the heater hoses and could still feel a little warmth. Not hot, but just a little heat. I did not think it would hold pressure that long.

FELLO FABO MEMBERS, PLEASE BARE WITH ME THROUGH THIS. I am in panic mode and some of my data may be a little off until I get tips from yall to help me a long.