The day I long dreaded, and perhaps others equally hate, is finally here. I received a notice that my vehicle must be tested to meet emissions standards. While it's an annoyance for a car enthusiast like me who modifies their car, I'm certainly not alone. In fact, 33 states have some sort of emissions program either because they've opted to, or because the EPA requires them to.

While some states have partial emissions tests based on where you live, in some states any and all motorists are required. We all know (or should) that California has among the most stringent air pollution standards, so its no surprise that vehicles there must undergo a smog check every two years. Similar programs exist in the northeast, where motorists in Delaware, Massachusetts, New Hampshire, New Jersey, New York, Rhode Island, Vermont, and Washington DC must all have their vehicles checked for excessive emissions. All of these requirements stem from the 1990 Clean Air Act amendments.

While some states scan a vehicle only by its On Board Diagnostics (OBD) 2 port, some states also employ oxygen sensors for vehicles older than 1996, to determine if their exhaust matter is too foul for standards. Ironically, many times it seems that it is the older vehicles that are spewing more oil, more carbon, and more pollutants than newer vehicles, but some states insist on only checking the engine computer to determine if there is a fault.

Those who modify their cars to add horsepower may also find themselves in violation of local laws, especially if the car is registered in California. CARB laws there limit what modifications can be done on a vehicle and any illegal modifications could mean the seizure of that vehicle.

If you're living in a state that requires smog checks- what's your least favorite thing about them?