Our long-term Jetta TDI has 4300 miles on it now, and even though it's been in our local VW dealer's service department twice due to faulty seatbelt sensors, today's news of the Jetta's win as Green Car Journal's 2009 Green Car of the Year gives us another reason to smile when we see our blue TDI sitting in the parking lot. We've been achieving fuel economy numbers around 41.5 miles per gallon so far under our normal driving habits, and we're impressed with how powerful this engine is while still being quite economical.

“The Volkswagen Jetta TDI rose to the top as Green Car Journal’s 2009 Green Car of the Year for some very important reasons,” says Ron Cogan, editor and publisher of Green Car Journal. “Hybrids have dominated the discussion of environmentally positive vehicles in recent years. The highly fuel efficient, 50 state emissions certified Jetta TDI shows that advanced clean diesel has arrived and is poised to change this dynamic. With its affordable price point, refined ride and handling, and high fuel economy, the Jetta TDI shows that hybrids now have a strong competitor in the marketplace.”

Congratulations, TeDI. Click through the post to read Volkswagen's official press release.

It may sound odd to you, but the Renault-Nissan Alliance hasn't produced any modern V6 Diesel engines - so far. After all the alliance, will have a decent engine to go with their 10th anniversary next year.

The first Diesel V6 engine developed and produced by the Alliance bares the code V9X. It is based on dCi common rail technology, and know-how derived from the 2.0 dCi straight four engine (year 2005).

BMW has officially announced pricing details about the 3-Series and X5 diesels which will be making their way into American showrooms within the next few months. The 335d will be priced at $44,725 (including a $900 tax credit) while the X5 xDrive35d will command $52,025.

Both of these cars are powered by a twin-turbocharged 3.0-liter inline-six which will pump out 265 horsepower and 425 pound-feet of torque. These cars will use urea injection and a particulate filter to clean up the NOx emissions. BMW says that the urea tanks can hold 5.5 gallons of fluid which will last about 15,000 miles. The urea will be replenished at the regular 10,000-mile service intervals (which are free of charge for the first 50,000 miles).

As far as fuel economy goes, the 335d is rated at 23/36 miles per gallon with a range of around 560 miles and the X5 35d should be able to go for 585 miles obtaining 19/26 mpg ratings.

+ AutoblogGreen: BMW officially announces new 335d and X5 xDrive35d diesels

If there's one automaker who seems to be on an increasingly upward trend lately, it's Hyundai. The Koreans took the world by storm with their eight-cylinder, rear-drive Genesis sedan, and the Hyundai folks have now released another bit of engineering to compete more closely with other worldwide automakers.

Hyundai's new four-cylinder diesel R-Engine will be available in both 2.0 and 2.2-liter displacements. The 2.0 produces 181 horsepower and 289 pound-feet of torque while the 2.2 puts out 215 horses and 398 pound-feet. Both engines are more powerful than Audi's new 2.0 TDI engine (170 hp/258 lb-ft).

The first vehicles to get these engines will be SUVs and large sedans sold in Europe, since the R-Engine meets Euro-V emission standards. No word on if this engine will ever make its way to the States, mostly due to our stricter emissions requirements. And to think, we'd love to see a Genesis Coupe with one of these powerplants under the hood.

Honda CEO Takeo Fukui announced at the last North American International Auto Show that his company would bring its first ever diesel engine to the USA in 2009, with most speculating that Acura’s TSX would be the first application of the powerplant.
 
Now various sources are reporting that the i-DTEC TSX has been put in the cooler indefinitely, presumably because the automatic transmission-equipped version of the has been unable to pass emissions testing. While the same source says that the six-speed manual-equipped car was able to cut the EPA mustard, Acura believes that offering the diesel TSX without an automatic option would greatly hurt demand for the vehicle.
 
Meanwhile the V-6 version of the car is reportedly being “fast-tracked” to make up for the diesel lack. That’s potentially good news for TSX fans but doesn’t do much for the growing legions of diesel-lovers in North America.

+ Vtec.net

The folks over at Motor Trend have gotten word that GM is currently talking about the possibility of fitting its 4.5-liter Duramax V-8 turbo-diesel under the hood of the Cadillac CTS. Their sources say that fitting the engine would be relatively easy, so long as Cadillac uses the raised hood found on the new-for-2009 CTS-V.

GM says that this engine is capable of producing more than 310 horsepower and around 520 pound-feet of torque. This engine is also said to meet the tough 2010 emissions standards, making it legal in all fifty states. If the V-8 were fitted in the CTS, this would be a good way to bridge the gap between the base car's 304-horsepower V-6 and the 556-horsepower supercharged V-8 in the CTS-V.

Since this engine already exists, as does a transmission capable of managing all of the torque, little investment would have to be spent on this endeavor. A move to a diesel CTS would also make sense in light of the proposed CAFE regulations mandating that automakers have a 35 miles per gallon average by 2020.

+ Motor Trend: Scoop! Cadillac CTS May Get V-8 Diesel Option

Since the Audi Mileage Marathon is essentially a contest to see which team of journalists can achieve the best fuel economy out of each vehicle, it's only fitting that some rules and regulations are put into place. Each car is fitted with a data logger that tracks the fuel consumption and average speed of each car, so even if we were to reset the in-dash trip computer, our overall results would not change. Points are awarded for the best fuel economy and the highest average speed, with more weight put on economy.

A team of IMSA officials traveled along with the Audi folks and monitored all fuel stops. Teams are not allowed to add any fuel themselves, and only one tank of gas is allotted per day. Just before we reach the hotel each night, we stop off at a Shell station where the IMSA folks fill the tank, record how much fuel was used, and seal off the fuel door with a signed sticker.

As for car modifications, we were told that the tires were inflated to the maximum pressure to give the best fuel economy. Bob Massa, a Michelin spokesperson, told us that even if we over-inflated the tires, it wouldn't do us any good, as the specific low-rolling-resistance tires outfitted on these cars were made for optimum economical driving. One team did, however, tape up the front end of a Q7 to eliminate any sheetmetal gaps, though these modifications did not improve their numbers in any way.

Click through the gallery to see some of the IMSA folks regulating our drive, and stay tuned for more impressions from the Mileage Marathon.

After having taken over for my colleague Steve Ewing here at the Audi Mileage Marathon, we have successfully embarked on our first day of travel here in Wave 3, having journeyed from downtown Denver to Durango. Along our day of driving, my new co-driver, Roosevelt Gist and I clambered aboard Audi Q7 #1, a number that would sadly not prove to be prophetic for our first day’s mileage.

Throughout our day’s journey we remained at higher altitudes, a factor that inevitably came into play even with forced-induction engines like our fleet of Audi TDIs. That said, our mileage struck us as very impressive, as we eeked out an unofficial figure 29 miles per gallon—this, despite basically spending the entire day above 6000 feet and as high as about 11,000 feet. Although official mileage results have not been tabulated through the use of the mysterious black boxes mounted beneath the load floor in the cargo hold (we’ll learn our day’s ranking later this morning), we hear that others have garnered average highs of as 30-31 mpg on their dashboard readouts.

(Click through to read on)

Hard at work racking up high mpg numbers on Audi’s epic TDI drive across the country, our own Chris Paukert has managed to sniff out some juicy details regarding a new derv-burner that’s headed State-side.

Audi officials have confirmed that the A3 2.0 TDI, in front-drive configuration only, will be headed to the U.S. market as soon as next fall for the 2010 model year. The A3 diesel will run the same basic engine as can be found in the current Volkswagen Jetta TDI, which manages to get away with not using urea injection technology because of lower NOx emissions.

We’ve also been hipped that Audi may be bringing the A4 TDI to our market, though that deal hasn’t yet received final approval. Both the 3.0-liter and 2.0-liter diesel engines could be in play for this application, though the higher loads on the smaller powerplant could necessitate urea to clean up the NOx. Having spent some time with a European specification A4 3.0 TDI, we can safely say that we’d be in favor of having that sedan in the States – A3 diesel sure sounds like a winner in today’s car buying climate as well.

This was indeed a nice surprise. After spending the past four days behind the wheel of a Q7 3.0 TDI in the Audi Mileage Marathon, we were given the opportunity to drive around in the not-for-America TT 2.0 TDI.

Audi has talked a lot about how they want to convey the message that diesel-powered cars can be sports cars, too. If the TT isn't enough proof for all of the nay-sayers, just look at the R10 TDI Le Mans car which takes home win after win. In fact, the Audi folks are running the R10 on pure bio-diesel these days.

The 2.0-liter turbo-diesel is the same engine found under the hood in our long-term Jetta TDI which just arrived. This powerplant is good for 170 horsepower and 258 pound-feet of torque. In our test TT, the power is routed through a six-speed manual transmission and is put to the pavement via Quattro all-wheel-drive. The Audi folks claim that the TT TDI will go from a stand-still to 60 miles per hour in 7.5 seconds and that observed fuel economy will be somewhere around the area of 44.3 miles per gallon. Judging by the numbers we've seen in the A3 2.0 TDI this week during the Mileage Marathon, we think that under conservative driving, MPGs could rise up to as high as 50.

(Click through the post to read more.)