There are both mobile and stationary sources of pollution and California has done a great deal about the latter. As a result, while the air is somewhat cleaner, the business community complains that too much burden has been placed upon them. The new smog check system will significantly reduce auto pollution by promoting better maintained vehicles, both through more effective testing and by reducing smog certification fraud. Opponents criticize better testing by arguing that new cars pollute so much less than 5 or 10 years ago that we don't need a new system. While it is true that newer cars pollute less, the key to their ongoing performance is proper maintenance.
New cars can deteriorate fast and then the benefits of new fuels and engines are lost.
This is what an effective smog check system guards against. The new system is technologically more effective because it more accurately simulates actual driving conditions. The old equipment only measured idling. The new equipment also measures acceleration and cold start emissions. This advance should be hailed.