I had a customer, women with an old Jetta. I told her to check the antifreeze ,as it was going to be cold. She called me and said that she filled the antifreeze but now the car ran poorly., could she come by?
She had filled the engine oil up to the top with antifreeze. Dumped about 3 gal out of water, antifreeze, and oil out of the engine, dropped the pan and wiped out the inside,refilled the oil and she drove it home.
She also filled it with diesel fuel, ran poorly then also.. The car outlived her..