Bad smelling fluid leaking from dash

Question

today i went to my car (1981 Honda Accord)and there was a puddle on the drivers side floor mat. it is slightly oily, light brown and has an awful sour smell. the windows were open before the leak, so it is possible that someone may have thrown something in my car, but there are stains running down the underside of the dash, so i kind of doubt it.The car seems to still be running fine. for now. (Other info: the car has no air conditioning system, and the oil, brake fluid and clutch fluid levels look fine) Any help would be great!

Answer 1

maybe you knocked over a drink and didnt know it,,probulaly milk or some diary product...

Answer 2

Was it hot outside something might be melting under there.sour smell it's hard to tell. GOOD LUCK I sure would like to know

Answer 3

I was going to say coolant leaking from heater core, but coolant would normally be yellowish-green or some other bright color, and would not be brown unless severely neglected.

Although, if somebody used plain water in the radiator, that could explain both the rusty color and leaking heater core (split from freezing, corrosion, or shot rubber hose).