I already replaced the one you mention its called cylinder crankcase coolant drain plug its small. The freeze plug is next to that plug its threaded and has 22 mm nut in the middle.my car also has small nonthreaded freeze plugs. As for the issue I have I cannot remove my leaking freeze plug because the 22 mm hex is corroded causing the leak and I cant turn it, so its off 2 the mechanic to spend a good amount of money.....I tried hitting with flathead screwdriver and mallet but no luck.
