Diesel emissions are checked every 2 years here in WA state. They only check for opacities. My '85 300D had to go through it a month ago and passed with flying colors. This was my second time since owning the car. The first time it still had all of its CA emissions garbage on it including the oxidizing catalyst. The second time none of it was operational, including the EGR and the OC, and it ran cleaner than the first time I had it checked.
It's all bull$#!t.

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DJ


84 300D Turbodiesel 190K with 4 speed manual sold in 03/2012