If you need a smog check, Ontario Smog can take care of it. Chances are you need a smog check if:Youre renewing the registration of your vehicle (required every other year for vehicles older than 4 years)Youre registering the vehicle for the first time in the State of CaliforniaYoure selling your vehicleYour vehicle is not diesel powered, electric, natural gas powered and over 14,000 lbs, a hybrid, motorcycle, or trailerYour vehicle is a gross polluter