Engine 1991 mustang gt automatic

I did the checklist, like I said I added coolant because it had barely any, I need to do a leak down test. I believe I cranked it until there was no coolant present in the cylinders "leaking in cylinders' or the fuel is so dirty it is getting dirt/rust and blocking the regulator. I'm not the best mechanic but I can read and use the book. This is what I'm marveled. I'll keep you guys updated don't want to waste your time