Everybody wants clean air. Most everybody wants to drive. When you drive a vehicle with a internal combustion engine that engine omits harmful pollutants to the air. Vehicle manufacturers design their power train control systems to lower these harmful emissions and provide good drivability. A smog test verifies the function of these systems.
Castner's Auto is now A STAR certified Smog Test and Repair Station. I'll update this page soon but in short the STAR program is what the Test Only/Gold Shield programs have evolved into. Being a STAR station means you can test any vehicle that needs to be tested. If you happen to have an DMV renewal that says Test Only on it that vehicle can also be tested at a STAR station.
DCA/BAR's website: http://smogcheck.ca.gov