I urge anyone who is considering buying a TDI to compare it to the insight on fueleconomy.gov for air quality ratings...making the assertion that the TDI is cleaner is wrong, and a simple search will show you that.

And for the reason why tdis hold there value so well, I will say that I think their prices are bloated, I would much rather save 1000 dollars buying an insight than a golf tdi. But that's just me.

Tdi
 

I drove a new Golf TDI 5-speed a couple years ago and nearly bought one -- I really liked the torque and FE, but a few concerns came up:

• Reliability
• Costly Maintenance Schedule
• Emissions

-Check Consumer reports for the reliability odds on different components.
-It requires Full-Synthetic oil, and the timing belt change is more frequent than the average model.
-I used to be a big Diesel proponent, but as SVO mentioned, the emissions are terrible. The "Clean Diesel" emissions system is better (not available in VW cars in the U.S. yet) -- but it's a new technology (my guess is they'll put the Urea injection design in the next model -- which requires re-filling it periodically). Honda has a design in the works that requires no Urea.

For running costs, and emissions -- there are better choices.

RH77

I know a number of people who have TDI's, I've also owned/worked on two older VW diesels, and grew up with other VW's in the family.
Their CV joints wear out quicker then any other vehicle I've ever seen, along with their suspension struts, their timing belts wear out about as often as a honda (90,000 miles) but to change the timeing belt you need a handfull of VW only tools, I also just talked to a guy who had a 2004 I think it was, who said it was burning thru sensors, and he busted a timing belt that cost him a head rebuild and a tow.
I've recomended them to a few people, but mostly if they live out of town and tend to drive 15+ miles each time they start the car, drive less then that and getting a gas car makes sense to me.

Great suggestion.
03 and older can run semi synthetic oil (Mobil 1 or similar) 04 and newer is fully synthetic and all of them have a 10k oil change interval. I would run fully synthetic oil in any car I bought for the life of the engine and better mpg's. Yes the timing belt is every 100k, not sure what most gassers are, I know our Toyota Sienna is 80k and cost a bit more to have it changed then the TDI. If you mean between the gasser and diesel versions, the timing belts have the same change interval, so that must be a VW thing.
It depends on what your looking at, diesel does have more NOX (smog), but far less CO2 (ozone), personally I would rather have ozone above us and smog down low. I have heard the urea system does require a fill like every 100k (the life of a car in the US) Not sure what VW is going to use.
Also the typical life span of a diesel engine is about 1.5 times or greater then that of a gasser so I took that in to consideration when we bought ours.

If choosing to ignore the major emission component in order to sustain the current "No proof to CO2 adding to global climate change" mantra of the US government, then by all means use the US government's number. If you wish to consider the total impact, and not merely pick and chose emissions you want, then the diesels are better (well, less harmful) than the alternatives.
The Argonne National Laboratory has some interesting data on total well-to-wheel emissions of some different energy sources . Biodiesel (on a kWh to kWh basis) is less environmentally harmful from a total emissions quantity standpoint than some "green" technologies such as natural gas, hydrogen (both liquid and gaseous), grid electric (using the US national average energy mix), ethanol and such. Only renewable electricity (solar, geothermal, tidal, wind) and nuclear had lower total emissions.

You state things just as deceptively, without actually talking about the issues you seem to bring up.

Gasoline engines are much better for air quality, you do not seem to debate that.

However, for GHG emissions, you claims "diesels are better." This is deceptive because CO2 emissions correlate directly to fuel used and the carbon content of the fuel, so, for example, when you compare two cars, you cannot simpy say diesel is better, because my car gets better gas mileage than yours, and allowing that the carbon content of the fuels is not too much different, has lower GHG emissions than yours. On top of that, it also has less sulfur and particulate emissions than yours.

However, unfortunately for TDIs, diesel has a higher carbon content than gasoline (https://www.epa.gov/otaq/climate/420f05001.pdf), so, my car has even lower GHG emissions than yours.

If you want to count "ALL" emissions (as you say), I guess VW may win once we factor in the BS emission levels.

Particulates (soot)
 

Another concern is the concentration of fine particulates or soot. High concentrations are responsible for exacerbation of breathing problems, most of which has been a spike in Pediatric Asthma.

It could be argued all day which chemical emission is the worst and how to control it, but as I'm sure some have realized, there isn't one answer to the question.

A Diesel Golf is going to emit less CO2 than similarly-sized competitor. If you can get 50+ MPG in a Golf, go for it -- but of course consider other options as you are now :thumbup:

Another thing, nobody mentioned the "Ego" emissions of the Passat :sigh:

RH77

EPA already controls for this. They use Carbon content to adjust for engine efficiency. For instance, if a 02 4cyl m/t Camry gets 27mpg combined, and a 02 4cyl m/t Jetta diesel gets 45mpg combined, the Jetta releases ~40% less Carbon than the Camry does. :thumbup:

Diesels emit more PM and NOx than the equivalent gasoline powered car, which emits more COx (x=1,2) and HC. PM<2.5 and HC are both carcinogenic, NOx contributes to smog formation, and CO is toxic w/ exposure being limited to 35ppm in the states. Carbon dioxide may contribute significantly to regional environmental change. Etc... Regarding the EPA emissions ratings, as long as it doesn't influence Americans in obvious ways, it's not a pollutant right? :p

I would like to point out that most of the information for diesel is based on LSD or low sulfur diesel at 500ppm of sulfur. At every pump I have seen and almost everywhere across N.A. you will find ULSD or ultra low sulfur diesel at 15ppm or less. This reduces the particulate emissions and obviously greatly reduces the sulfur output as well. This change also allows for newer models to employ some NOX reducing equipment that will get it at or below even some of the better gassers.

Again I am not knocking gassers; each has its strong points and should be chosen based on many personal consideration, to many for someone else to choose for you. Honestly if someone had a 1.3L diesel weighing around 2000lbs it would get phenomenal mileage. Remember the VW’s are all 3200+ lb vehicles.

Unbeweevabo !!
 

SVO"Boy".....
Hard for me to believe that one guy that doesn't even own a diesel can blow soooo much Smoke !!!!