us engine manufacturers will have to ensure that all heavy-duty trucks operating in California have computer systems to diagnose and warn drivers of emission problems. This first regulation of its kind in the country was issued by California Air Resources Board (carb) on July 21, 2005. carb said the us Environmental Protection Agency is also going to approve a similar rule for diesel and gasoline engines.

The installation of the diagnostic system, to be phased in for big trucks from 2010 to 2016, is related to tougher pollution control rules due from 2007. It will cost nearly us$132 per truck.