Whats a difference in OBD1 and OBD2? And what do I have to do If I want to change my 95 civic EX which have OBD1 to OBD2? And one more question B18C1 is OBD1 and OBD2 so how is it going to work? Can I swap B18c1 without doing anything to my OBD1? So here are some of my stupid question that I am trying to find aswer for. Please just answer them?