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New Cleaner Diesels Arrive In California

It’s been a long time coming, but buying a new car with a diesel engine is now an option in all 50 states, including California.

Thanks to CARB (the California Air Resources Board) and the lack of pollution advancements in diesel engine technology for the past little while, car shoppers in The Golden State couldn’t get a new car with a diesel engine. Not only did this prevent people from obtaining cars that were more fuel efficient, it also meant that if Californians wanted to run an alternative fuel like biodiesel, buying used was their only option.

The first of the new breed available will be VW’s Jetta TDi, although this will most certainly be followed by Mercedes’ own line-up of diesels. The Jetta in diesel guise provides a combined 33 MPG for the sedan, and a slightly higher 34 MPG for the SportWagen. That’s pretty impressive for a car the size and weight of a new Jetta (VWs have been on the porky side for a while), so for certain kind of buyers, say new families, a clean diesel Jetta SportWagen could be a very good answer to their transportation questions.

A large part of cleaner-running diesels in 2008 is the fact that the government reformulated what goes into diesel fuel; in this case, they lowered the amount of sulfur allowed, so that gave automakers a leg up. In the case of the cleaner-burning diesel engines, both VW and Mercedes are using a catalytic converter that stores a diesel engine’s high NOx emissions. This, although prosaic and mundane, is more than a bit of a breakthrough, given that the first answer from Merc was to inject urea into the exhaust header. (The way we understand it NOx, or nitrogen oxide, can be chemically bound to urea, rendered inert, and then flushed out the tail pipe of the car. The new catalytic converter is far more elegant.)

If you want to go beyond low-sulfur diesel, consider putting some biodiesel in your tank. But note that your vehicle warranty may be effected affected for fuels that are blended with more than 20 percent biodiesel — check here for details.

So, the new clean diesel Jettas are here — prices start at $21,990.

9 Responses to “New Cleaner Diesels Arrive In California”

  1. Ron, Good question on how the cat works.

    Near as I can tell, MB started calling it a “storage catalyst” a few months ago, but I never saw any explanation as to what that meant.

    The gist of what I got was that it was a cat like that found on gasoline powered cars, only with different materials coating allowing it to do its chemical work.

    I’m not sure if it’s vanadium or not, but I do know that it’s not platinum (as in gasoline fueled cars).

    From what I read, the new diesel cats will function in the same way as existing cats, i.e. it’s part of the exhaust system, and you don’t have to worry about it (unless it corrodes, gets plugged, gets holed by a rock etc etc etc).

    I do know that the new gen of diesel engines are using particulate filters that have to be replaced. Not sure of the service interval for that, but as I recall, it’s somewhere in the 100K range, so not all that often.

    If anyone out there DOES know, please write in

  2. Affected, not effected.. I’m not even a journalist and something like that shouts out. Anyway 33mpg isn’t really that great .. double that and you’re really talking. HOW does the CC “store” the Nox? is it converted to a powder or a solid.. or is this a euphemism and it isn’t really “stored”? I would expect the CC to need renewing flushing whatever. plus it probably uses vanadium or other rare earth metal extracted at great damage to the green. Earth.