Newer vehicles can be guilty of spewing harmful emissions

New test taps into built-in computer on late-model cars to look for problems

If identifying the worst polluting cars, trucks and sport utility vehicles were as simple as standing on the side of the road looking for fumes, there would be no need for AirCheckTexas. But it’s not, and there is.

“You can’t tell which vehicles are polluting the most just by looking at them,” said Hazel Barbour, Mobile Source Programs Manager with the Texas Natural Resource Conservation Commission. “The only accurate and fair way to find out is to test vehicles so owners can get those polluting vehicles repaired. Even newer vehicles, if not properly maintained, can emit higher levels of the pollutants that form ozone smog.”

Beginning May 1, every gasoline vehicle 2 to 24 years old, registered in Harris, Collin, Denton, Dallas, or Tarrant Counties, must pass the new AirCheckTexas emissions test along with the annual vehicle safety inspection. Depending on the model year of the vehicle, it will have to pass one of two new tests.

Model year 1996 or newer vehicles must pass the On-Board Diagnostic II, or OBDII test. While the engine is running, the OBDII taps into the vehicle’s built-in computer that monitors the fuel, ignition, and emission control components. This computer is constantly making adjustments to the systems’ operations. “The OBDII test uses the vehicle’s computer to accurately check all the emissions-related parts,” said Maj. Robert Burroughs, head of the Vehicle Inspection and Emissions Division for the Texas Department of Public Safety. “This test is so sophisticated, it can detect problems before there’s a serious and potentially costly failure.”

When there is an emissions-control problem, the “Check Engine” or “Service Engine Soon” light appears on your dashboard. At the same time, a diagnostic trouble code is stored in the computer’s memory so a repair technician can easily retrieve the code and fix the problem. “If you don’t make the repairs early, you’ll end up paying a lot more later,” said Burroughs. “That’s just one of the benefits of AirCheckTexas- saving people money in the long run.”

The emissions testing program is part of the state’s plan to clean up the air in Texas’ most polluted regions, so they will comply with health standards of the federal Clean Air Act. Houston and the Dallas-Fort Worth areas are both considered by the U.S. Environmental Protection Agency to be in violation of federal health standards for ozone smog.

“This is the most important action individual Texans can take to help clean the air we breathe,” said Chairman Colleen McHugh, Texas Public Safety Commission. “For our health, everyone must take responsibility and make sure their vehicles are well-maintained.”

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