Honda Civic fails the smog test

Honda Civic

My car was bought new in 2010. We have been out of the country for a year and now we are back to US to a new state. As per the state rules we took our car for the emissions. But even after driving for 150 miles it still fails the test. My car needs to pass the emissions in order to get the new registration done. please advice.

Post the year of the vehicle and the computer codes that are causing it to fail when you get a chance and we can dig into the causes.

In the meantime hear is a cheat sheet on how to pass the emissions test.