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Tier 2 Bin 5 Diesel Jetta Makes its US Debut; Available in 2008

Volkswagen of America unveiled its cleanest diesel yet for the US, the Jetta TDI, at the Washington, D.C. Auto Show. (Earlier post.) The new clean diesel, which meets the 50-state EPA Tier 2 Bin 5 / CA LEV II emissions standard, will be available to the US market in the spring of 2008.

The 2.0-liter diesel develops 103 kW (140 hp) of power. The Jetta TDI—one of VW’s first BLUETEC products—uses a lean NOx trap to reduce NOx emissions by up to 90% percent instead of using urea Selective Catalytic Reduction.

The engine management system in the Jetta changes operating modes periodically to treat the NOx that has been stored in the catalytic converter. A particulate filter in the exhaust system further reduces emissions.

The goal of the BLUETEC initiative of Audi, Mercedes-Benz, and Volkswagen is to establish the concept of BLUETEC as a uniform label for clean and highly fuel efficient diesel-powered cars and SUVs with 50-state compliant engines. Technologies individually developed by each manufacturer serve to reduce NOx in particular.

For car models of the Passat class and smaller, Volkswagen is proposing its new lean NOx trap catalytic converter. At λ of greater than 1, NOx is captured and stored; at λ less than 1, NOx is released and reduced. Ultra low-sulfur fuel is a necessity, and fuel consumption will increase as a result of catalytic converter regeneration.

Larger and heavier models feature urea Selective Catalytic Reduction (SCR) catalytic converter (continuous) with the use of an aqueous solution such as AdBlue, transported in an additional tank made from stainless steel or plastic.

Another VW BLUETEC clean diesel—the Tiguan compact SUV—will also be available in the US in 2008.



I can only hope that the Passat will be offered with a diesel and DSG in about the same time frame..

fyi CO2

When will MPG figures stated? estimated pricing?


I have the Passat 2.0TDI stationwagon with DSG. Mileage figures have been around 5 liters/100 kms in hwy, around 6,5 in city driving (which I do really little because parking is a pain in the ... here, I rather walk or take the bus or metro). So, about 47 MPG in hwy, 36 in city. The numbers are according to the on-board computer. My Passat is the non-Bluetec version.


I just read a report that said the true cost of gasoline (after you factor in all the subsidies) is $15.14 per gallon.

Just charge that. We'll hit the 20% goal (and then some) literally overnight. And probably also fix the budget deficit.


Oops, sorry, wrong thread.


Yessir, here come the diesels. All you anti-diesel wingnut losers can SUCK IT DOWN! This goes out to all of you, Andrey, Willemsen, George, all of you: MUWAHAHAHAHAHA! :D


My next car will be either running biodiesel, or a next-gen hybrid. I'd like to know what the MPG figures on this will be. That it doesn't use AdBlue is a plus.


I think the EU version of this Diesel is 170 hp. Thats quite a hit for the small NO2 gains.


Isn't it funny all that mess with the Blue-Tec Diesels?

Not only that this type of diesel fuel required is not yet available (US) nationwide (<10 ppm Sulphur as maximum content; current US diesel has up to 500 ppm). Also these "super-clean" diesels don't meet the Californian standards (ie can not be sold in the stated which adopted these standards), and will - as stated - consume more fuel due to higher backpressure and catalyst regeneration.

From a CO2 perspective, I doubt that such an engine will have a smaller footprint than an ordenary gasoline engine. Of course, shifting consumption to diesel might be a good thing from an economic point of view, as the US would then no longer need to buy refined gasoline on EU markets, and the EU buying diesel on US markets (and then de-sulphurizing it).

Of course, the US will import the carciogenc soot issue with these diesels, as the finer particles will penetrate deeper into the lung, with higher chances of causing cancer...

In the end, diesel might end up with an even higher net cost here in the EU - hopefully at such an extent, that not even the heavy subsidies (tax breaks) on diesel fuel will hide the fact, that it's already more costly than gasoline.

Of course, running a diesel engine with Veggie oil (*not* biodiesel) would be a benefit, but then again, there just ain't enough oil crops for sustained mobility by such means... (And, of course, diesel engines right now - especially the ever more highly sophisticated ones - can not run un-modified veggie oil; old-style, pre-chamber, non-turbo diesels can run on almost anything; but then, you also don't really care what's being exhausted from those engines...


I have a concern with diesel. With greater use of diesel for the light vehicle sector (in large part frivolous usage) does that not put pressure on diesel prices for our transportation and farming sectors (vital). The last thing I want in an oil crunch is some rich jerk in a diesel SUV driving up the cost of diesel for our farmers.

Having said that it seems easier to produce biodiesel than biobutanol.

Alex Pine

"Also these "super-clean" diesels don't meet the Californian standards"

"The new clean diesel, which meets the 50-state EPA Tier 2 Bin 5 / CA LEV II emissions standard, will be available to the US market in the spring of 2008."

what are your data sources?
if you don't like diesels, what do you like?


Richard, the whole point of the T2B5 compliance is that this vehicle will meet the requirements for ALL 50 STATES. It is the current model (an example of which I own) that does not meet the requirements of the CARB states.

By the time this vehicle is on sale, substantially all of US on-road diesel fuel will be ULSD. It is already all ULSD here in Canada, but the US dragged its feet. No doubt the initial sketchy availability of ULSD has something to do with this engine not being available until 2008.

Carcinogenic soot? The Bluetec system includes a particulate trap. I have heard reports that the exhaust coming out the tailpipe has less particulate in it than the air going in the engine air intake. Mercedes did a demonstration of holding a white napkin at the tailpipe of their E320CDI Bluetec. It remains white. This will be simply a non-issue. By the way, gasoline engines emit extremely small particulate, too ...

And how is the CO2 footprint of an engine that uses ~40% less fuel going to be equal to that of a gasoline engine? YES the diesel fuel contains ~10% more carbon, but it doesn't offset the fuel consumption improvement. My 2006 Jetta TDI PD (without Bluetec - No de-nox catalyst and no particulate filter) uses around 5.2 - 5.5 L/100 km during normal driving. The gasoline version uses 9 ~ 10 L/100 km.

Why the statement "vegetable oil and *not* biodiesel"? I do not understand it. The main ingredient in the biodiesel "recipe" is vegetable oil. The second ingredient is (usually) methanol, which is currently made from natural gas, but still it is ~75% biofuel. And, you can use biodiesel in the newer diesel engines without trouble. I do. I have B20 (20% biodiesel) in the tank right now. I run B100 in the summer, but can't do that in winter ...



Us refineries produce an excess of diesel that is currently shipped to Europe. If we start using more at home we can just stop exporting the excess, plus refineries can be tuned to produce more diesel if needed.


VW, if you are listening, please offer diesels in all of your models. Jetta Diesel: nice to have you back old friend!


Voltswagen, please get off the Oil Company bandwagon and produce an efficient Diesel Engine for high frequency generators for series hybrids like the Volt, in the 13-50 kw region needed. A standard small commuter car series hybrid only needs a 13 kw generator, and efficiencies of over 100 mpg are quite possible with wheel motors. The engine only needs to supply the average power needs of the vehicle (typically energy required at 60 mph) and does not have acceleration or torque requirements and pollution controls are more simple due to the constant rpm.

Sid Hoffman

ULSD ( 15 ppm max, 10ppm avg ) started phasing in the USA in July of 2006 and was at 50% of diesel pumps by October 2006. To say that it isn't here is an absolute lie.


Bow to CARB and EPA. They once again managed to force auto manufacturers to bring new substantially cleaner vehicles to US and eventually to global market.

Anon: clean diesel is welcomed by anyone, even me, believe you or not.

Things really are getting heated-up. Who will win on US market: diesel with NOx adsorber or lean GDI with NOx adsorber? In which segment? How hybrid drivetrain or (even more interesting)coming two-mode hybrids will affect this competition?

We live in exciting times.

Green Car Congress

"Voltswagen, please get off the blah blah blah wagon and blah blah blah Diesel Engine for blah blah blah i'm a whiny bitch 13-50 kw region needed. A standard blah blah car series hybrid i have no life blah blah. The engine only needs to blah blah average power needs of the vehicle (now im just jacking off in public) and does blah blah acceleration or torque blah blah pollution i need to get a life blah blah."

Wow man. That was deep. Next time you feel you have the moral high ground to tell VW how it run its business, do us all a favor and keep it to yourself.

Yours truly
Green Car Congress


Nope, W.Heath is exactly right. Series genset is where the IC engine is meant to go next.


The Prez actually mentioned biodiesel before ethanol last night. This is a first!

fyi CO2

Thanks for the series hybrid perspective Heath. Others occasionally write "blah blah" and contribute nothing to this forum.

Rafael Seidl

Doug -

I suspect the reduced power rating is not so much a function of the additional emissions equipment as of the relatively low cetane number of US diesel fuel. In layman's terms, his is a measure of how easily the fuel will ignite in hot, pressurized air. For reference, EPA requires a CN of 39.5 for #2 diesel, California insists on 45. In Europe, the current standard is 51. Biodiesel is a little higher that, xTL liquids much higher still. Blends of petrodiesel and these alternatives lie in-between.

Longer ignition delay translates to inferior control of the injection process, higher engine-out NOx and PM levels and more combustion noise. To counter that, you have to reduce the amount of fuel you inject, i.e. sacrifice some horsepower. Switching fuels will not automatically give you more power, you would need to reprogram the injection system for that.

Richard -

(a) NOx store catalysts do indeed require very low sulphur levels in the fuel. ULSD, which was introduced in the fall and is now the only grade being sold for on-road use in the US, contains 15ppm. EPA mandated the transition precisely to enable lean-burn NOx aftertreatment. Even in Europe, where emissions standards for diesels are not yet as strict as in the US, on-road diesel fuel may contain no more than 50ppm today and 10ppm by 2010. Countries with a high proportion of diesel vehicles are already meeting the future standard today.

(b) Tier 2 Bin 5 is equivalent to California LEV II, meaning any vehicles that passes this hurdle can be sold in all 50 states. This is critical to sales volume and profits for LDV diesels in the US.

(c) Diesels do emit about 20% less CO2 than the same vehicle fitted with a similarly rated gasoline engine when put through the same standardized drive cycle. This is just basic thermodynamics: a higher compression ratio and no throttling losses.

(d) T2B5 diesels will all feature wall-flow DPFs, which render harmless 98%+ of all engine-out particulates. Also not that there are many other sources of particulates, including those small enough to penetrate the alveolae in the lungs.

(e) Diesel fuel is denser than gasoline and therefore contains about 12% more energy per gallon. On a per-BTU basis, US on-road diesel and regular gasoline actually cost about the same. The relative financial benefit to the driver will indeed be lower than in Europe, where diesel is taxed a little less heavily (hardly a subsidy) than gasoline. However, the superior thermodynamics of diesel combustion still mean each BTU gets you ~10% further.

(f) Using SVO on a modern diesel engine may overrev the turbo and cause cavitation in the injector nozzles. You could end up with major damage after just a few thousand miles. Btw, SVO/WVO produces extremely high PM levels except in specially adapted engines. It should not be used from an emissions point of view alone, even if it is possible and legal to do so with old indirect injection engines.


An engine could easily be adapted to work on SVO with low emissions etc.

The problem is that in order to make the design easily, a universal standard of SVO formulation must be agreed upon, which isn't going to happen given the different oils, crops and other feedstocks available worldwide.

An engine tolerant of a wide variety of SVO types would be possible but a challenge to design.

Sid Hoffman

Just to clarify Rafel's point "e", it's a little disingenuous to say diesel fuel has 12% more energy per gallon without pointing out it makes 12% more CO2 per gallon too. It's no surprise diesel weighs about 12% more per gallon.

This is why there's no point in talking about miles per gallon, the discussion should either be miles per pound or miles per dollar depending on which discussion you're having. This also makes it easier to compare to non-liquid fuels as well.



Please refer to Point C regarding those CO2 emissions. The greater amount of CO2 per gallon is only part of the equation. Diesel engines are still more thermodynamically efficient and thus emit 20% less CO2.

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