I did a search and couldnt find much. Just ran my truck through today and it barely passed. For the test we just have opacity here, and I got 37% out of 40%. I am worried because I have 370s sitting here and I am waiting on dvs. Would these mods make it worse next time? I am sick of the dmv, non of my cars like to pass emissions

 

If you stiffen up your star wheel setting for the test (or better yet, install a valet switch) you should be able to pass no problem.

 

I didn't Arizona required testing for diesels, I guess that one good thing about Cally-fornia I don't have to do that smog thing on my truck.

 

I totally forgot about a valet switch! Thanks.

Winkle, it depends what county you live in whether you have to pass emissions.