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Q: Failed smog test

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The reason my minivan didn't pass the smog test, they tell me, is because the catalytic converter log isn't filled. They told me to drive it on the interstate for an hour between 55-60mph. I did this several times, but still didn't pass the smog test. What do you suggest that I do to solve this problem?

Hello. The catalytic converter acts as a filter for exhaust gasses emitted from the vehicle. This purpose of this is to reduce the pollutants that are expelled into the environment. The first thing you could try is adding a catalytic converter cleaner to your gas. You’ll want to allow this to run through the catalytic converter and see if it passes the smog test. You could also try using a higher grade of gas and this might help your vehicle pass the smog test. If this doesn’t work, it may be necessary to replace the catalytic converter itself. If you are unable to pass the smog test and need to replace the catalytic converter contact a certified technician, such as one from YourMechanic.

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