I have a 99 honda civic with a B20 Block out of a 98/99 honda crv 2.0 with a B16 head. Has a DC header with no place for aO2 Sensor. Can't pass emisions, cause it says it has to high of HC & to high of readings NOX. What should I do?

 

there must be something wrong somewhere.

it's a lot of work, but you could swap the engine to stock for emissions, and then swap it back afterwards. that'd be a PITA though.

 

I bought it with this engine in it. So I don't have another engine. Got any other ideas of what to do?

 

The HC and NOX, is that the amount coming out of the exhaust pipe you mean? If so, how's your catalytic converter? Is it in good shape? If not, it might not be doing its job right. Also, are you saying you have no O2 sensor? Because without an O2 sensor the ECU can't tell what's coming out of the engine, and therefore can't tune itself to fix that if possible.