Diesels pre 98 are smog exempt in California but if you convert a gas car to diesel in California it has to be ref'd to make sure all the requirements were met. As soon as thats done it gets a diesel title and is exempted from smog. I was on alldata and actually was able to find the test procedures for all of the EGR related emissions components. Hopefully this weekend I can get down to business a test the function of some of these components unfortunatley it looks like my transmission will be coming back out so I can figure out how to mount the VR speed sensor.