I do believe that there is a serious negative perception about diesel in the US and combined with low availability of diesel pumps/stations + higher cost/gallon - There seems no incentive to move to diesel.
I am no expert but how does diesel stack up against gasoline on the environmental front ?
This VW-TDI-engine-enthusiast FAQ page suggests diesel's latest engines and emissions systems are better than gasoline when all dimensions are considered -- but US regulations are still gasoline-normative:
Diesels are great engines, but hard to come by in the US. In Europe the majority of cars, from small ones to big limousines have Diesel engines these days.
The most vexing problem, particulate emissions, has been solved with particulate filters, that burn of the collected particulate cake occasionally, by heating it up to 600 C.
In the US Diesel cars are only available from VW and Mercedes. Due to the recent availability of low sulfur Diesel fuel in the US, new models have come onto the market. VW offers the Jetta and Touareg with the latest technology (common rail) Diesel engines. These are direct-injection turbo-charged, and have excellent fuel economy.
However, I've heard that due to fleet emissions standards, VW will only be selling Diesels for a few years. Which is probably true for Mercedes as well.
Personally, I've been driving Diesels forever, and love the efficiency and torque you get from them.
I routinely get 40-45 MPG on the highway in my 2003 VW Jetta TDI with an automatic transmission while driving between 70-80 mph with the air conditioning running at max. I have never had a problem with diesel fuel quality or availability.
My choice of a diesel was not simply to achieve a lower fuel cost per mile. Maintenance costs and reliability are also better due to the lack of certain systems within a diesel engine (i.e. no spark plugs, alternator, etc.).
It's important to remember that diesel's carbon content (generally what people actually care about these days when they talk about fuel efficiency) is about 15% higher than gasoline's. So the CO2 emissions of your Jetta are more comparable to a 35-39mpg gasoline car. That's still good, but not that much better than a typical compact (say a Civic or Corolla). My '99 Saturn gets about 32-35 under similar highway conditions.
Basically: there's nothing wrong with your car, and it's a fine choice (as long as you keep it tuned! Diesel's particulate emissions can go south really fast if they're not maintained well). But don't be fooled by volume metrics. It's still no Prius.
Why wouldn't a diesel car have an alternator? You need to generate electricity for all the electrical systems (lights, ac, radio, etc). And instead of spark plugs, you have glow plugs with diesels.
Bought a 2009 VW Jetta TDI in April and have yet to have a tank of diesel that will cause my average MPG curve to have a negative slope. Coming from an 1986 Mercedes 300 SDL who would soot at ever pedal stomp, I cannot find a way to make an exhaust soot cloud in the TDI, even under 0-60 race conditions. Diesel prices have been less than mid/premium unleaded in California since I bought the car.
Let's remember that the testing cycles in Europe and the US are not the same, and that the 57 MPG number isn't explained (well, I just skimmed... but a search didn't find much).
Is it a combined or just highway rating?
In general, the EU cycle gives numbers 30% higher (and even more if you forget to convert imperial gallons back to US gallons).
So while diesel has benefits, lets be careful with the numbers.
Does anybody else feel that stuck-in-the-mud-ness increases for every technological generation? Seems the more thing advance, the more people say "right, THIS is how it should be" and never want to move on. Diesel cars are a good example. FFS, the automobile is less than a century old for the normal person. And yet, people have these ridiculous ideas about what is the "normal" fuel to put in them. And are thus resistant to superior technology.
I'm no expert but I believe the sulfur content is higher in North American diesel, but that's not too hard to handle, I think that's the old excuse and there are fairly clean ultra low sulfur diesels you can now buy. To pass California emissions, you need to put some sort of aqueous urea tank in to the exhaust system like an AdBlue or BlueTec and those cost a couple thousand dollars (I want to say it's like $3000 on a diesel sedan like a Subaru or the 320D)
I'm not sure why the costs are so high, it may be a patented technology, there isn't anything terribly exotic in it though.
If you can legitimately get in the 40-45mpg range, it's still a pretty good deal. A Lexus RX hybrid still only can get like 30mpg.
Because there's a negative perception hump to get past in the usa. I tried suggesting a diesel, and everyone complains about how dirty it is and other myths.
There are diesels that get even better millage, like the Audi A2 with a mileage on it's diesel model ranging from 80 to 120 mpg. I never understand why car manufacturers don't make aerodynamic body designs for their cars. A honda insight with a diesel engine gets similar mileage.
[+] [-] UsNThem|16 years ago|reply
I am no expert but how does diesel stack up against gasoline on the environmental front ?
[+] [-] anamax|16 years ago|reply
There are fewer stations that have diesel than have gas in many places, but where is diesel availability low enough to matter?
Trucks get diesel somewhere.
[+] [-] gojomo|16 years ago|reply
http://www.tdiclub.com/TDIFAQ/TDiFAQ-5.html
[+] [-] car|16 years ago|reply
The most vexing problem, particulate emissions, has been solved with particulate filters, that burn of the collected particulate cake occasionally, by heating it up to 600 C.
In the US Diesel cars are only available from VW and Mercedes. Due to the recent availability of low sulfur Diesel fuel in the US, new models have come onto the market. VW offers the Jetta and Touareg with the latest technology (common rail) Diesel engines. These are direct-injection turbo-charged, and have excellent fuel economy.
However, I've heard that due to fleet emissions standards, VW will only be selling Diesels for a few years. Which is probably true for Mercedes as well.
Personally, I've been driving Diesels forever, and love the efficiency and torque you get from them.
[EDIT] This article gives a good overview of the state of Diesel in the US: http://www.popularmechanics.com/blogs/automotive_news/423558...
[+] [-] papersmith|16 years ago|reply
[+] [-] tumba|16 years ago|reply
My choice of a diesel was not simply to achieve a lower fuel cost per mile. Maintenance costs and reliability are also better due to the lack of certain systems within a diesel engine (i.e. no spark plugs, alternator, etc.).
[+] [-] ajross|16 years ago|reply
Basically: there's nothing wrong with your car, and it's a fine choice (as long as you keep it tuned! Diesel's particulate emissions can go south really fast if they're not maintained well). But don't be fooled by volume metrics. It's still no Prius.
[+] [-] elai|16 years ago|reply
[+] [-] porkcharsui|16 years ago|reply
[+] [-] MikeCapone|16 years ago|reply
Is it a combined or just highway rating?
In general, the EU cycle gives numbers 30% higher (and even more if you forget to convert imperial gallons back to US gallons).
So while diesel has benefits, lets be careful with the numbers.
[+] [-] sho|16 years ago|reply
Also, it is MPG, not MGP.
[+] [-] whatusername|16 years ago|reply
Agreed about the stuck-in-the-mud --- I think we all do it to some extent - but it can get very frustrating.
[+] [-] plainspace|16 years ago|reply
[+] [-] Nelson69|16 years ago|reply
I'm not sure why the costs are so high, it may be a patented technology, there isn't anything terribly exotic in it though.
If you can legitimately get in the 40-45mpg range, it's still a pretty good deal. A Lexus RX hybrid still only can get like 30mpg.
[+] [-] masomenos|16 years ago|reply
[+] [-] elai|16 years ago|reply
There are diesels that get even better millage, like the Audi A2 with a mileage on it's diesel model ranging from 80 to 120 mpg. I never understand why car manufacturers don't make aerodynamic body designs for their cars. A honda insight with a diesel engine gets similar mileage.
[+] [-] robin_reala|16 years ago|reply
[+] [-] sp332|16 years ago|reply