The passage of the Clean Air Act Amendments of 1990 mandated that the Agency put into place a program that would monitor the performance of the emission control system on all automobiles beginning with the 1996 model year. This emission control program is know as On-Board Diagnostics. If the vehicle's computer determines that a problem exists, information is stored in the computer's memory and a light on the dashboard will illuminate. While this light does not indicate an emergency situation, timely response to the malfunction indicator light can not only reduce pollution, but can also save consumers time and money. Potential savings can result because the OBD system is designed to inform drivers not only when something in the emission control system fails, but also when it begins to deteriorate.
Early diagnosis followed by timely repair can often prevent more costly future repairs.
For example, a poor performing spark plug can cause the engine to misfire, sometimes going unnoticed by the driver. This engine misfire can, in turn, degrade the performance of the catalytic converter. With OBD detection of the engine misfire, the driver would be faced with a relatively inexpensive spark plug repair. However, without OBD detection, the driver could be faced with an expensive catalytic converter repair in addition to the spark plug repair. The OBD system will also provide far more information to auto technicians than they have ever had before to help them diagnose problems and properly repair your vehicle.