HomeGreen BusROUSH CleanTech Propane System Achieves HD-OBD Certification

ROUSH CleanTech Propane System Achieves HD-OBD Certification

The California Air Resources Board and the U.S. Environmental Protection Agency certified ROUSH CleanTech’s propane autogas fuel system as complying with the heavy-duty onboard diagnostics (HD-OBD) regulation that has been in play for diesel and gasoline engines.

The HD-OBD certification developed by CARB, covers all ROUSH CleanTech’s propane autogas-fueled vehicles that have Ford 6.8L 2V and 3V engines, including school buses. ROUSH said its 3V engine is also the first and only propane autogas engine that is available for class 4 to 7 vehicles that is certified to the optional low nitrogen oxide (NOx) level of 0.05 g/bhp-hr.

CARB approved the regulation in July 2016, to reduce motor vehicle and engine emissions for onboard diagnostic systems that were installed on 2010 and newer model-year diesel and gasoline engines that power vehicles weighing over 14,000 pounds GVWR. Alternative fuel engines had been largely exempt, but as of the 2018 model year, manufacturers must implement diagnostic systems and monitor NOx after-treatment.

The OBD systems use onboard computers to monitor emissions systems in-use for the entire operable life of the engine and detect malfunctions of the monitored emission systems. The system illuminates an indicator light to notify the vehicle operator of a malfunction, and stores fault codes.

“Vehicles powered by a fuel other than gasoline or diesel should no longer be considered alternative,” commented ROUSH CleanTech President Todd Mouw in a statement on Tuesday. “As shown by the regulatory agencies’ decisions to require all fuels in its HD-OBD certification, propane autogas and others like compressed natural gas, are moving into the mainstream.”

He added that the company is focused on delivering for customers the best alternative-energy solutions, to assist in meeting economic, as well as environmental sustainability goals.

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