It can throw an engine fault code if it finds the catalyst to filter before reaching the rear oxygen sensor in your exhaust system to adjust fuel curves or Air to Fuel ratio. You might remove the muffler but manage the noise at legal levels but you're still not in the clear. How can I find out if the upgrade parts I want to use are California smog legal, and won't fail the . Exhaust headers, not to mention the entire AIR Air injection system is an "emissions component". Your vehicle will fail the smog inspection even before the tailpipe exhaust is checked. The cookies is used to store the user consent for the cookies in the category "Necessary". If you pass the emission test, chances are you get a penalty for illegal car noise. I think its worth the money for a number of reasons. Muscle cars from the late 1970s may be less desirable than their siblings from 1975 or earlier, often due to smog requirements.In California, for instance, a car must pass rigorous inspections for emissions equipment. Performance cookies are used to understand and analyze the key performance indexes of the website which helps in delivering a better user experience for the visitors. A: I agree! The purpose of a smog check is to make sure that the cars on the road are running cleanly. A library with 40 decibels. Motor vehicle exhaust systems or parts thereof include, but are not limited to, nonoriginal exhaust equipment. Smog checks are similar to window tint or not having a front license plate. Installing Aftermarket Parts: I want to install some aftermarket performance parts on my car's engine but I'm worried I might have a problem passing the CA smog check. The exhaust system doesnt get inspected after the CAT. Jan 13, 2018. Having ditched the muffler, you may immediately question legal complications. Launched in 2001, this resource focuses on the 1990-1999 Mitsubishi Eclipse, Eagle Talon, Plymouth Laser, and Galant VR-4 platforms. It costs between $50 and $250 to make the parts. Do you need a muffler to pass smog in California? Granted, they have every right to, particularly if you are breaking local noise ordinances. Installation of a cat back exhaust system is easy. A muffler captures it from the catalytic converter. document.write(AffiliateBanner);