I have a simple question that may seem dumb to most of you. What is the different between OBD1 and OBD2 and which do I need for a 99' Civic Ex. I've searched this but I can't find exactly what I need to know.

 

You have a b18c im assuming right?

 

I don't have one yet but, I am looking into them for my car.

 

Obd is on board diagnostics, but what matters to you is emissions. Obd1 is up to 95, and obd2 is for cars 96+. As the years get later, the obd changes. For Civics up to 91 is obd0, 92-95 is obd1, 96-98 is obd2a, 99-00 is obd2b, and the rest don't matter to me so I never cared to look. But the main question you need to answer is do you have to go for emissions? IF you DO, then you NEED an obd2 gsr engine and ecu to pass emissions. Otherwise the emissions will be old standards and your car will fail. But if you don't need to go for emissions then just get an obd1 gsr engine. Less emissions to deal with and are easier to find and cheaper.

 

Well, I live in Maryland so I have to get my emissions done every couple of years. I just got it done actually, so could I buy a engine with obd1 then get obd2 on it later when I need emissions or would that be pointless?

 

Where at in MD because my car is registered on the eastern shore & there they dont do emissions & I have an obd1 Ls in my car...

Emissions is really only for highly populated cities. (i think)

 

You can't just make an engine in to obd2 like magic. It'd be swapping parts over, mainly things like sensors and stuff which are on the obd2 head. So just find an obd2 gsr and go from there...