Mostly, my 335d was originally sold/purchased in San Diego CA. In California manufacturers are required to put an additional warranty on the car for 7/70K miles. So its actually written as an additional policy that is in effect from the in-service date of the car. Even when the car leaves a carb complaint area the warranty remains in effect, much like the factory warranty. So even though the car has been registered in CA, AZ and now TX it still has the carb warranty in force, as my car is 5 years in service and 54K miles.

I have had the MAF, Exhaust Pressure Sensor, DPF differential pressure sensors, Vacuum hoses for differential sensor, etc. All covered under the CA emissions warranty. (all replaced to fix an EGR triggered SES) however the SCR tank was not covered under CA warranty as its not a listed item. (temp sensor died a few months ago), I was to get the SCR tank partially paid by BMW "good will". I'm not unique in this, I've read of several others having the same thing happen on a CARB registered 335d, which is how I found out I could ask my service adviser if they would cover the items under the CA emissions warranty.