Introduction
This is a guide from a frequent TDI owner who DIYs all maintenance so you'll hear the good, bad, how to fix the bad, and common modifications. Whether you're new to diesels or know a lot, this page will let you quickly compare Volkswagen and Audi diesel, why I prefer diesels over hybrids, and learn a little about the renewable fuel biodiesel. For more detailed information such as technical specs, maintenance intervals, recalls, technical service bulletins, and "how to" for your car, go to the bottom of that car's section for its detailed specs link, or refer to: 1000 answered questions: diesel FAQ and "how to" index (also linked through the blue button at the top).
Table of contents
Model specific new owner, buying guide, and catch up maintenance
checklists (see above)
Why a diesel car may be in your
future and basic FAQs
Why not a hybrid? TDI vs. hybrid
a3/b4 1996-early 1999 Jetta/Passat
a4/b5 late 1999-2005 Jetta/Passat, 1998-2006
Golf/New beetle
a5 late 2005-2006 Jetta and 2009-2010 Jetta sedan
2009-2011 Sportwagen
a6 2010-11 Golf
a6 2011 Jetta
Audi A3 TDI
VW Touareg TDI
Introduction to Biodiesel
If you think of diesels as the smoky, slow car from the 70's, think again. Today's diesels are clean burning, powerful, and reliable. The newest common rail technology cars are so quiet and clean that a bystander would never know the car is a diesel by the sound or smell. In fact, there's less soot on the exhaust pipe of the latest TDI clean diesels (the VW/Audi marketing name for diesel) than many comparable gasoline cars! Diesels account for about 50% of all new car sales in Europe and have much better fuel economy than a similar gasoline car. For example, the VW Lupo, a Europe-only subcompact Volkswagen, drove 20,000 miles around the world in a promotion, averaging over 80 miles/US gallon (2.5 liters/100 kilometers). A major concern for modern cars is improving fuel economy and emissions, so I believe that diesels will have a much larger market share in the short term North American market. Audi, VW, BMW, and Mercedes Benz all currently have multiple diesel models for sale in the US. In the long term cars will probably be hydrogen fuel cell or fully electric powered. In the far future we'll all be flying around on personal jetpacks circa the 1962 world's fair.
This section has both basic and advanced facts so I hope everyone can find something interesting. For a more advanced and detailed description of diesel mechanics, diesel systems, and turbos, refer to 1000 answered questions: how a diesel works, 1000 answered questions: turbocharging, 1000 answered questions: how a clutch works, and 1000q: how a DSG auto-manual transmission works. If you're interested in running biodiesel, please read 1000 answered questions: biodiesel.
Volkswagen Audi TDI in North America are turbocharged and intercooled 4 or 6 cylinder engines that use direct injection, a technology that is only now being put into a few gasoline cars. Larger/sportier diesel passenger cars like BMW or MB and trucks use 6 or 8 cylinder engines. The largest engine for North American TDI was the twin turbo V10 in the Volkswagen Touareg. Europe even had the option of the V12 VW Touareg TDI and Audi Q7 TDI!
Some of the major reasons why diesel engines get better mpg is because of the engine design and fuel. Diesel fuel contains more energy per gallon and run very lean (a higher air:fuel ratio) so they can do more work off less fuel. The combustion process also produces less waste heat, meaning more of the energy is translated into work. All diesels are high compression so the engine can get more energy out of each combustion cycle. Engine RPM is controlled by fueling and not a throttle, meaning parasitic pumping losses off the engine are reduced. Modern diesels are all direct injection, meaning the fuel is compressed under very high pressure and sprayed directly into the combustion cylinders. They are also all turbocharged, which can increase fuel economy, depending on engine design and power load.
Why not a hybrid? They're a good solution to reducing emissions and increasing fuel economy. However, I prefer the current diesels in the marketplace than the hybrids in the new and used car marketplace. There's a lot more to driving than fuel economy. If fuel economy were everything then you can't beat riding a bicycle! Why even bother mentioning hybrids on a diesel site? Because most people know that hybrids give great fuel economy but aren't even aware that there are diesel cars for sale in North America. Because of their high fuel economy, there will be some cross shopping between types.
The pros/cons of a diesel or hybrid are also effected by driving style and whether you make mostly short local trips or longer highway commutes. I also like driving manual transmission cars and there is no manual hybrid. (The Honda CRX coupe was recently introduced with a manual). Until they make a large Prius station wagon, the Jetta and Passat station wagons have an unbeatable blend of economy and cargo room. Compare the newest Jetta TDI sportwagen with 67 cu ft of max cargo room plus a roof rack with the newest Prius and 40 cu ft. Your fuel economy may vary and people boasting about their car normally give their personal bests. Diesel engines also take thousands of miles to break in before reaching peak fuel economy and this is reflected in new car testing. Below are some comparisons between a diesel vs. a hybrid. Ultimately it's a question of values and economy.
Although hybrids do have cleaner emissions and limited High Occupancy Vehicle (HOV lane or carpool) access, diesels that use the 100% renewable and homegrown fuel biodiesel have greener emissions than a hybrid. And while every little bit helps, I've found that the majority of those who tout the lower CO2 emissions of a hybrid are not sincere in making other lifestyle choices to further reduce CO2 emissions. City living so you can use mass transit and drive far less, small apartments so you build and heat less empty living space, and vegan diets to reduce the high CO2 emissions from meat/milk/eggs production are all common, affordable, and could have a much greater effect on conservation than just buying a hybrid with no other change in lifestyle. It's not reasonable or correct to claim righteousness when your change in lifestyle is convenient to you while rejecting the validity of another's values. Somewhere there's a bike riding freegan (non homeless people who eat non spoiled food out of public trash) wearing used clothes criticizing a Prius driver! I care about the environment but don't want a bike riding freegan lifestyle since my values are different and are my own. Again, it comes down to a matter of values and economy. To make a direct comparison to a gasoline non-hybrid, the Volkswagen Jetta TDI has about 25% lower CO2 emissions than the basic 2.5L gasoline engine Jetta.
A diesel may also be more economical in the long run over a hybrid. Comparing the same year Prius and Jetta, a Prius has better average reliability. But the Jetta has better safety ratings, standard safety equipment, and should last longer. (A light diesel can last up to 300-400,000 miles with regular maintenance and upkeep because it has cooler running temperatures, operates at lower RPM, and diesel fuel is an oil. Start/stop can be harder on engines than constant normal running.) It's more economical to buy a diesel and drive it for 20 years with minor repairs but you won't have the newest technology. A dust-dust analysis of energy put into a Prius favors a new car past a relatively low mileage if newer technology comes out (in reality that car is sold to another person as used) but buying new cars every few years will cause you to pay all of the depreciation cost. The Jetta diesel has excellent aftermarket support since it shares suspension and other parts with similar VW gasoline cars, letting you add an aggressive sport suspension or other aftermarket parts. What do you value and how much are you willing to pay for it?
The biggest disadvantage of hybrids is the additional cost and weight of the hybrid technology. The current generation of hybrids cost $3,000-10,000 more than a comparable non hybrid car, a cost that you will probably not recoup in fuel savings. The largest flagship luxury hybrids use V8 engines which use the hybrid label as a greenwashing gimmick. Many hybrids are also merely electric assist and not full hybrids, meaning that they cannot run on electric alone, reducing the advantages of buying a hybrid. The Chevy Volt is planned to have this capability but the estimated MSRP of the car is $40,000! The upcoming Fisker Karma, a lithium-ion plug in hybrid, appears to be a great car with exclusivity, style, and technology but with a starting price of $80,000 it's a niche within an expensive niche. The Nissan Volt is supposed to be a full electric car but it has a limited range. The Chevy Malibu mild hybrid had start/stop and a mild hybrid system but it was panned in reviews as not worth the additional cost, not well integrated, and was discontinued.
The manufacturers who make hybrids vs. diesel also have different ideas about luxury and
design. VW and Audi have class
leading interior design compared to the strange Prius or Lexus HS250h
interior. Compare the Lexus interior on the right with the Audi A3 interior below
left - the
A3's interior is much cleaner and richer. VW and Audi consistently have
class leading interiors. The Lexus has their "mouse" controller stuck onto the center
console and buttons and stalks scattered everywhere. While the higher
screen is easier to view, the driver's primary focus should always be
safe driving.
Hybrid also have compromises in the driving experience to maximize fuel economy. For example, a leading hybrid uses cheap, narrow, and hard tires to maximize fuel economy and the EPA test mileage. These tires are among the worst rated on tirerack's survey! Everything else being equal, hard narrow tires increase fuel economy but reduce handling and braking. In hybrids with regenerative braking, the limiting factor in braking is not braking force, but tire grip. Any more braking force cannot be put to the ground to slow the cars or else the tires will lose their grip and force electronic stability control to reduce braking. Using grippier, wider tires with more traction would increase handling and braking but at the cost of reducing fuel economy.
I believe that driving pleasure and choice of car should be a balance of your needs and wants between sportiness, comfort, fuel economy, price, practicality, and safety, and that hybrids sacrifice some of these qualities. I believe that people can enjoy great freedom and pleasure when driving and that cars are more than just an appliance that takes you from point A-B as economically as possible. Those are my values. Ultimately, your values are what matters so test drive a Volkswagen TDI and then drive a Prius and compare them yourself. If your greatest priority is fuel economy and you can't tell the difference in handling, driving feel, interior quality, and design, then getting a Prius or another car is honestly a good option. Again, the best car for you is one that matches your needs, not mine.
The future will have much better gasoline hybrid cars, but I feel that there is a lot lacking in the current generation.
I think it will only be a matter of time before you see electric-diesel hybrids
with fuel economy in the 60-80 mpg range. By then, electric-gasoline
hybrids and full electric cars will have advanced as well, so I can only say
with an educated opinion what is now. For a different perspective, here is the conclusion from an article in Autoweek comparing the
Prius, a Jetta TDI, and a few other cars in a real world fuel economy test.
The testers made the same conclusions as myself on driving feel and real world
fuel economy vs. EPA estimates. http://www.autoweek.com/apps/pbcs.dll/article?AID=/20060424/FREE/60417021/1008
"TOYOTA PRIUS: 8.3 gallons of regular gas at $2.599/42 mpg vs. EPA highway rating of 51 mpg
Well, it didn’t make its 51-mpg EPA highway estimated, but 42 mpg on a long road trip would please most American drivers...That instant feedback loop, monitoring economy in short increments of time and distance—not to mention letting the driver see exactly where the energy is going to and coming from—is a big part of why Prius drivers are so prone to telling the rest of us, “You have to drive it differently.” We found that isn’t quite true; the Prius responds to the same economy-minded driving techniques experts have been advising for 30 years or more. ...The difference in the Prius is it offers up immediate gratification of the video-game variety, right there on the dashboard, no waiting to fill the tank and do the math yourself. ..It did really well. It just wasn’t the mileage champion.
VOLKSWAGEN JETTA TDI: 7.0 gallons of B20 biodiesel at $2.749/ 49.9 mpg vs. EPA highway rating of 42 mpg
Our fuel station was offering up B20 biodiesel, 20 percent of which comes from vegetable oil, animal fats and other sources, meaning that from an environmentalist’s perspective the German diesel didn’t just beat the Japanese hybrids, it trounced them. Not only that, it had more than half of its 14.5-gallon tank left at the end—it could have made the same trip again without refueling! Our example was pretty much a stripper, absent even the usual VW trip computer, so we had no instant feedback loop on our performance. Maybe if we’d had that, we could have nudged the economy from 49.9 mpg into the 50-mpg range...at highway speeds its 177 lb-ft at 1800 rpm and 100 hp at 4000 rpm feel stronger than the Toyota
and smoother than the Honda. The diesel spins harder than the Vette at 80 mph, running at 2500 rpm or so, but still it is a long-legged German car with autobahn-able credentials.
For comfort, quiet and highway handling, our drivers found the TDI had significant advantages over every other car in the test. It would have been our choice, in other words, for an easy daytrip on the interstates, regardless of fuel economy. And we topped the hybrids by driving with just a little attention to fuel economy, not making it an obsession."
Here is a video review from edmunds - "based on value, comfort, and
fun, the 2009 VW TDI is the smarter choice and the car we choose over the
current Prius." If they had reviewed the station wagon they would
have found much more cargo room plus a roof rack and no penalty in economy due
to identical weight. Below is another review comparing the Audi A3 TDI and
VW Jetta TDI vs. Smart vs. the Insight, Prius, Smart, and Fusion hybrids.
a3/b4 VW refers to the mk3 1996-1999 Jetta (a3) or 1996-1997 Passat (b4). These are usually the least expensive cars to buy because of age, mileage, and standard features. Since they're already depreciated, you won't pay to hold the car but be prepared to budget for "catch-up" maintenance. These are the first Volkswagen TDI sold in the US (there were non TDI diesels as early as the 70's). They share a 1.9L 4 cylinder 90hp/149 lb-ft engine and are manual transmission only. All cars are front wheel drive. Jetta is 4 door sedan only but the Passat was available as a station wagon or sedan. Because of a 28 gallon fuel tank, the wagons can go over 1000 miles per fill up! Expect 38-50 mpg by the average driver in real world conditions. They weigh less but have less luxury and safety features compared to later cars..
See 1000q: mk3 Passat/Jetta TDI new owner checklist to see a detailed list of common problems and immediate maintenance these cars need, below is a summary. For a full list of "how to" maintenance on these cars, refer to 1000q: mk3 "how to" index.
Pros:
-Usually the least expensive due to age and trim levels
-The 1996-1997 passat wagon has the largest fuel tank (~28 gal) and longest range of
all the VW diesels, 1000 miles/tank is possible
-Easiest for do it yourself maintenance, simpler systems
-Lightest weight, similar engine as later cars
-Steel oil pan reduces chance of damage to engine from road damage
-Excellent choice for running biodiesel
-Front airbags
-Loosest emissions standards
-Manual transmission only
Cons:
-Manual transmission only, not really a con for most since the automatic
transmission delivers lower fuel economy and they were available on the
newer cars
-Loosest emissions standards
-The least luxury and safety features, most miles due to age. Look for
rust in the wheel wells, bottom of the door, and windshield "a"
pillar.
-Not much cheaper than next generation cars depending on the used car
market.
-4 lug wheels mean less choices for aftermarket wheels.
-Jetta has front disc brakes but rear drum brakes. (Rear disc brakes can
be retrofitted)
-ABS optional, most TDI don't have it.
-Only front airbags, side airbags not an option.
Short list common problem areas (see 1000q:
mk3 jetta/passat
new owner checklist for a detailed long list)
-Cracked vacuum or pressure hoses due to age and wear, the small hose in the ECU
should always be checked before replacing a bad ECU, see 1000q:
ecu hose for details.
-Cloudy plastic headlight lenses, see 1000q:
polishing headlights for the solution
-Windows fall down/stick due to broken window regulator clips,
see 1000q: window regulator
recall for details
-Failing door handle on the Passat due to wear and poor design, see 1000q:
door handle fix for details.
a4 refers to the 1999.5-2005 Jetta, 1998-2006 New Beetle, and 1999-2006 golf. b5.5 (or b5) is the 2004-2005 Passat TDI. These are the most common TDI because more cars were imported to North America than other generations. The 1999.5-2003 engine is now rated at 90hp/155 ft-lbs torque because of a newer turbo design which gives better low end power. All Passat have 2.0 8v engines with 134 hp/247 ft-lbs torque. 2004+ a4 cars feature "pumpe duse" BEW TDI engine rated at 100hp/177 ft lbs.
Both manual and automatic transmissions are available but the auto transmission gives lower fuel mileage and typically does not last nearly as long as the manual. All cars are front wheel drive. Jetta available as station wagon after 2002, Passat wagon available 2004-2005 (auto trans only with Passat). MPG est. 35-42 city/45-50 hwy. Later cars after 2002 have 80,000 and 100,000 mile timing belts that can be retrofitted to earlier mk4 cars. Budget some "catch-up" maintenance. See 1000q: pumpe duse vs. direct injection to see some mechanical differences between the pumpe duse and non pumpe duse cars.
See 1000q: mk4 Jetta/New beetle/Golf new owner checklist to see a detailed list of common problems and immediate maintenance these cars need, below is a summary. For a full list of "how to" maintenance on these cars, refer to 1000q: mk4 "how to" index and 1000q: mk4 how to index for pumpe duse cars. For the 2004-2005 Volkswagen Passat TDI, see 1000q: B5.5 Passat "how to" list.
Pros:
-Newer interior/exterior styling and more features than earlier cars.
-Newer variable vane turbo design and misc. small engineering and design improvements.
-5 lug wheels mean much greater choices for aftermarket wheels and brakes than
mk3 cars.
-All cars now have disc brakes in front and rear.
-Front, side airbags, ABS standard in North America.
-Side curtain
airbags and stability control optional, standard in later years.
-Some cars have ESP (stability control) or ASR (low speed traction
control).
-Longer 100,000 mile timing belt standard on later mk4 cars can be retrofitted to earlier mk4
cars.
Cons:
-1999-2003 auto transmissions higher than normal failure rate, 2004+ auto transmissions
are much better
-VW Passat station wagon automatic transmission only, all auto transmissions give less mileage
than manual
-Aluminum oil pan can be punctured by road damage, bottoming out on railroad
crossings, or improper towing, damaging engine
-Later style "pumpe-duse" engines prone to camshaft wear. See 1000q:
camshaft inspection for more details. This may be related to thinner
oil, 5w-40 or thicker is recommended. Refer to 1000q: pumpe duse
engine oil for a list of approved engine oils. Check 1000q:
a4 body differences to see some differences between pumpe and non pumpe
duse body styles.
Short list common problem areas (see 1000q: mk4 Jetta/New beetle/Golf new owner checklist or 1000q: mk4 Passat TDI new owner checklist for a detailed long list)
-MAF (Mass Air Flow sensor) often slowly fails, creating gradual loss of power, see 1000q: MAF FAQ and 1000q: MAF testing and replacement
Major model year changes:
1999: Beetle adds side turn signal behind front fender. ABS standard on new beetle
2000: Immobilizer anti-theft device in key
standard, some models receive clear side marker lights, trunk entrapment inside release latch added,
brake wear indicator light on dashboard
mid 2001: side airbags standard in Jetta, head curtain airbags
optional in Jetta, standard in Golf, trunk entrapment latch standard
2002: Jetta available as TDI wagon, new 2 din stereo system with optional cd changer
option, monsoon stereo is also changed, cd player standard on GLS, Golf GL now available in 4 door
2002-2003: ESP stability control becomes an option on all models
2003: New wheel styles introduced, base GL now includes power windows/locks, cd player, and
cruise control standard (all base cars), GLS now includes alloy wheels and moonroof standard.
2004: Pumpe duse engine introduced (click here to see the differences
between direct injection and pumpe duse), Passat now available with diesel
engine in the US, Passat wagon now available as TDI (auto transmission only),
side head curtain airbags standard, Auto transmission now 5 speed instead of 4
speed (the
5 speed is much more reliable), Jetta is slightly restyled (click here to see the
differences), Monsoon premium stereo standard on GLS
2006: ESP stability control standard in the US
For a full list of "how to" maintenance on these cars, refer to 1000q: mk4 a4 "how to" index and 1000q: mk4 a4 index for pumpe duse cars or 1000q: 2004-2005 Passat TDI how to list.
See 1000q: 2005.5-2006
Jetta pumpe duse checklist and buyer's guide for the earlier pumpe duse VW
Jetta TDI (sedans only)
See 1000q:
2009 2010 VW Jetta diesel buyer's checklist and guide for detailed dealer
invoice price, MSRP, options, and other buying tips on the newer common rail
engine VW Jetta TDI (sedans only)
a5 refers to the late 2005-2006 and 2009-2010 Jetta sedan. While it also includes the 2009 wagons, they are in a separate section below for organization. Due to emissions, not available for model year 2007 or 2008. They are among the best condition cars because they are only a few years old but are generally the most expensive. 2005.5-2006 TDI use the pumpe duse engines, 2009-2010 use the common rail engines. See 1000q: pumpe duse and common rail for technical descriptions of the engines. They also have the option of the DSG automatically shifting manual transmission, a totally different technology vs. the conventional automatic transmission found on most cars. Introduction of the independent rear suspension on Jetta. The new TDI has a federal income tax credit so check your local laws for any tax benefit or exemptions for high mileage cars.
See 1000q: a5 VW Jetta TDI "how to" list and FAQ for a list of "how to" and FAQ specific to these cars.
Pros:
-Nicest interior with more features than previous
generations, more luxury and standard safety features.
-New car smell and most have a known maintenance history.
-All TDI now use independent rear suspension for better handling and comfort.
-Common rail engine quiet, efficient, clean, and more powerful.
-Common rail engine available in a new car in all 50 states due to cleaner emissions.
Cons:
-Were more expensive because they are the newest and because VW moved their
cars slightly upmarket.
-There were potentially defective clutches on all early build cars, see
this defective clutch TSB
for details.
-Some DSG "auto" transmissions have bad flywheels,
see 1000q: DSG FAQ for details
-Not recommended with grease car "veggie oil" conversions.
Short list common problem areas (see 1000q:
mk5 Jetta 2005-2006 or 1000q:
mk5 Jetta 2009-2010 for a detailed long list)
-Dual mass flywheels having problems.
-Many 2005-2006 wear down their camshafts, see 1000q:
camshaft inspection for more details.
-All engines should use engine specific engine oil. See 1000q: pumpe duse oil
for more details for 2005-2006 models. 2009-2010 TDI must use only VW 507.00 spec oil, see
the 2009-2010 buyer's guide for a list of approved oils.
-Some 2009-2010 TDI have engine stuttering at certain throttle/rpm
positions that is probably linked to EGR metering and tuning.
See 1000q: 2009-2011 Sportwagen buying guide for wagon specific information.
The 2009 wagon was called a 5th generation car and the 2010 wagon was called a 6th generation car despite only being refreshed. See See 1000q: 2009 vs. 2010 TDI for a detailed list and gallery of differences. Even though the Jetta wagon is built off a different chassis, no longer resembles, and has different features from the VW Jetta TDI sedan, it's still called the Jetta for 2011. The pros/cons are the same as the a5 generation cars.
The Jetta Sportwagen is still built on a mk5 Jetta chassis so it didn't get the mk6 Golf upgrades like thicker glass or stronger chassis but it didn't get the mk6 Jetta sedan downgrades either, like loss of the independent rear suspension. It's sold in Canada as the Golf wagon and the rest of the world as the Golf variant but it's not built on a Golf chassis. See the buying guide for detailed differences and revisions over 2009 vs. 2010 vs. 2011.
See 1000q: 2010-11 VW Golf diesel buyer's checklist and guide for detailed dealer invoice price, MSRP, options, and other buying tips.
a6 refers to the 2010 and newer 6th generation Golf. It uses the same common rail engine as the 2009-2010 Jetta but in a revised next generation body. The new body features revised suspension and chassis tuning and is a total overhaul of the mk5 body. The 2010 Jetta station wagon sportwagen TDI still uses the mk5 body with some mk6 updates. VW considers it a mk6. The 2010 Golf uses the full new mk6 body. They also have the optional DSG automatically shifting manual transmission. The 2010 TDI have a federal income tax credit . Also check your local laws for any tax benefit or exemptions for high mileage cars.
See 1000q: 2009 vs 2010, mk5 vs mk6 TDI differences for a detailed list of differences between the 2009-2010 cars and 5th gen-6th generation bodies.
Pros:
-Golf and Jetta wagon have new generation styling and more standard features like touchscreen radio,
multifunction steering wheel, and bluetooth (USA).
-Common maintenance issues in last generation addressed
-All TDI use independent rear suspension for better handling and comfort.
-Common rail engine quiet, efficient, clean, and more powerful.
-Common rail engine available in all 50 states due to cleaner emissions.
Cons:
-2009-2010 TDI must use only Volkswagen 507.00 spec oil, see the buyer's guide for a
list of approved oils.
-Not recommended with grease car "veggie oil" conversions.
-Some 2009-2010 TDI have engine stuttering at certain throttle/rpm
positions that is probably linked to EGR metering and tuning.
See 1000q: 2010-11 Audi A3 TDI buying guide, FAQ, and checklist for detailed MSRP, pricing, options, and other tips.
The 2010 Audi A3 TDI is built off a longer mk5 Jetta a5 body and uses the same
engine and transmission as the other front wheel drive VW TDI. The chassis
code is 8p. It gets
different trim/interior, suspension tuning, and a longer hatchback body vs. the
VW.
The main advantage of the Audi is that you can equip it much higher than the VWs.
Some examples are the standard s-line exterior, dual
zone climate control, optional Alcantara suede interior, sport
package, or power seats. See the buying guide for more details. The 2010
TDI are also have a federal income tax credit.
Check your local
laws for any tax benefit or exemptions for high mileage cars.
Pros:
-Slightly nicer trim, can't really see it in pictures but you can touch and feel
it. Slightly nicer components like sharper HID headlights and LED running
lights
-Can option much higher than VW
-Halfway in size between Jetta sedan and wagon
-Brand name = image
Cons:
-Brand name = $$
-Uses 5th generation body even though the VW Golf gets the 6th generation body
-Everything should be better in the Audi vs. the VWs but it's not. Some
examples are the GPS system, base stereo, and free initial scheduled maintenance on the
VW.
See 1000q: 2011 Jetta TDI buying guide, FAQ, and checklist for detailed MSRP, pricing, options, and other tips.
The mk6 2011 Jetta TDI lost a number of features vs. the mk5 generation car
but it also lost about $1000 to address complaints that the last generation
Jetta were the most expensive Jetta yet. They also simplified the available
packages into just base and nav package. The car changed from independent
rear suspension to torsion beam rear suspension. See the buying guide for
detailed examples and pictures of the differences.
Pros:
-Refreshed styling over controversial last generation styling.
-Cheaper
Cons:
-Cheaper...torsion beam rear suspension, articulated trunk hinges, dashboard
plastics
See 1000q: 2009-2010 VW Touareg TDI buying guide for detailed info on the car like explanation of features and more useful info
The 2nd generation VW Touareg TDI (Touareg2) has an unbeatable blend of fuel economy, towing capacity, value, and cargo room. The only comparable cars are the BMW xDrive35d (X5 with diesel), Mercedes ML 350 Bluetec and GL 350 Bluetec, and Audi Q7 TDI. The big difference vs. other VW/Audi TDI is that it uses a 3.0L V6 TDI engine vs. a 2.0L 4 cylinder TDI engine. It uses the same engine as the Audi Q7 TDI but is shorter and has less luxury features and available options. It can tow more and can have a special order air suspension.
Pros:
-True 4x4 construction and capability
-excellent towing capacity (7,716 lbs) and ground clearance
-excellent fuel economy/power/weight ratio for SUV
Cons:
-While every individual car is different, they're about as reliable as the BMW and Mercedes
See 1000q: 2011 VW Touareg TDI guide for detailed specs, order guides, and explanation of features.
The 3rd generation VW Touareg TDI got a totally new body and interior for 2011. While the V6 TDI engine is carried over, the transmission is now 8 speeds and the car lost about 450 lbs which increases performance and fuel economy. The interior took a step up in luxury and is even bigger despite the exterior not growing much. There's also a hybrid Touareg.
Pros:
-same towing capacity and 4x4 capability as last gen
To dispel one of the biggest myths about biodiesel, it's not used grease or straight veggie oil. That's like saying gasoline is the same as crude oil. Biodiesel is a fuel for diesel engines that is made from refined and processed oil, fat, grease, and even algae. It's one of the most commonly used alternative fuels that will, in my opinion, gain more widespread use in the future. It's cleaner burning than petrol diesel, normally domestically grown and processed, and a 100% renewable fuel. It can be used in modern diesel engines and oil-fired home heating systems with little or no modifications. It's also biodegradable, less toxic than table salt, and with greatly reduced odor and emissions compared to diesel fuel. From an environmental perspective, it is greener than petrol diesel. From an engineering perspective, it lubricates better vs. ultra low sulfur diesel. From a geopolitical and national security perspective, it can be domestically grown and produced.
While it can never replace all the fuel needs of the world, it's important because research on biodiesel yields valuable knowledge on making biofuels and on future fuels like synthetic diesel fuel, because it's renewable, and because it decentralizes fuel production. By decentralizing fuel production and distribution, it's possible to have small scale refineries located very close to their retail fuel pumps. This reduces transportation costs as well. The main problem is the higher cost to produce biodiesel. It's sometimes cheaper and sometimes more expensive than petrol diesel depending on market conditions, government regulations, and subsidies for clean fuels. This is just a summary, for more details please see 1000 answered questions: introduction to biodiesel.
The viscosity of biodiesel is also much closer to of diesel fuel vs. veggie oil, reducing the chance of stressing the mechanical fuel pumps. Using biodiesel requires no modification to use in a modern diesel car. A grease car, greaser, or WVO car that runs on veggie oil requires minor modification to the car and must be started and stopped on diesel fuel to flush the fuel lines. If the fuel lines are not flushed prior to shut down, a grease car may not be able to start with veggie in the fuel lines. A negative of using pure biodiesel is that it gels at a higher temperature than diesel. Diesel fuel begins to gel at -20oF, 100% biodiesel without winterization begins to gel anywhere from 14oF to 50oF depending on its ingredients. Many retail pump biodiesel is 20% biodiesel 80% petrol diesel and won't suffer from these problems because they have winterization anti-gel additives and are cut with petrol diesel.
Biodiesel is also better for a diesel engine. There is no question that it lubricates the engine better than petrol diesel and has a cleansing effect upon the fuel system, cleaning out any old diesel build up. Because of the new ultra low sulfur fuel used in the US and Europe, using just 2% biodiesel will lubricate the engine and fuel pumps very well. Because the longevity of a well maintained diesel engine is already so long, the added lubrication will help guarantee a long engine lifespan. The only possible problem with biodiesel involves high percentage bio used with the post combustion injection and the particulate filters found on the newest TDI with diesel particulate filters. Read 1000q: DPF and Adblue filter FAQ for more on these systems. The newest generation engines are too new to know of any long term issues.
Another reason or its popularity is that it can be made inexpensively by the user. Its cost may be anywhere from 25 cents/gallon to $1/gallon if you make it from used grease from local restaurants that normally have to pay to have their grease removed. Please note that biodiesel making materials, processes, and equipment may be regulated by fire codes and is a potentially hazardous activity so always follow safe and prudent operating procedures. Always comply with any local, state, or federal regulations regarding your biodiesel making materials, processes, equipment, or biodiesel use.
For more information on making biodiesel at home, click here for 1000 answered questions: Intro to making biodiesel
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