How do you fix emission problems on 1998 civic?

To address emission problems on a 1998 Honda Civic, first, conduct a thorough diagnostic to identify the specific issue, such as a faulty oxygen sensor, catalytic converter, or EGR valve. Replace or repair any malfunctioning components as needed. Additionally, ensure that the air filter is clean, and perform a tune-up that includes replacing spark plugs and checking fuel injectors. Finally, running a fuel system cleaner may help improve overall engine performance and emissions.