California will soon start a statewide diesel emission program but I believe it starts with 1998 and later vehicles.
http://www.bar.ca.gov/80_BARResourc...ulatoryActions/FAQs for Diesels 1-8-09_GC.pdf
http://www.bar.ca.gov/80_BARResourc...ulatoryActions/FAQs for Diesels 1-8-09_GC.pdf