TDI clean burning diesel

[boosted475]

How does everyone feel about the new TDI cars that get more mpg and less emissions?

[Celtic Blue]

Originally Posted by boosted475

How does everyone feel about the new TDI cars that get more mpg and less emissions?

The new TDI's get lower mpg than the old ones.

[ksstathead]

See new Edmunds.com study for mpg. Emissions aren't even close.

Or are you saying the new TDI's do better than old TDI's? I assume since you came to a prius site, you meant to compare to Prius...

[donee]

Hi Boosted...,

As people have indicated they aren't. And the main reason is to reduce NOx, the peak combustion temp has to be reduced, and this reduces engine efficiency.

The urea injection turbo-diesels (not the VW TDI but other luxury brands) might be able tom improve mileage. This is done by improved fuel spray patterns, with higher fuel injection pressures.

[Tideland Prius]

Originally Posted by boosted475

How does everyone feel about the new TDI cars that get more mpg and less emissions?

A step in the right direction but still behind hybrids (even the Escalade methinks). THey're much better than diesels of old but anyone claiming that the new TDIs are as clean as hybrids have breathed in too much diesel soot. Maybe as clean as the Escalade but at Tier 2 Bin 5 they've just met the basic criteria all gasoline vehicles must achieve (this would be ULEV-II for the public). The Prius is Tier 2 Bin 3. The Honda hybrids are both Tier 2 Bin 2.

[Flying White Dutchman]

Originally Posted by boosted475

How does everyone feel about the new TDI cars that get more mpg and less emissions?

i feel the name "clean" is not correct

its more like "cleaner" then before but never "clean"

diesels are dirty..

also the new commen rail injected turbo diesels these "clean" diesels are.
not clean, just cleaner.
and i am not talking about co2 but real stuff like NOx

[patsparks]

Originally Posted by boosted475

How does everyone feel about the new TDI cars that get more mpg and less emissions?

Numb.

[wxman]

The slightly higher tailpipe emissions of the current generation of T2B5 clean diesel vehicles (mainly in the form of NOx) are at least partially, if not mostly, offset by the much lower evaporative hydrocarbon (HC) emissions in the fuel supply chain (diesel fuel is far less volatile than gasoline).

HCs are the most problematic pollutants in areas of the U.S. where unacceptably high ambient levels of ozone ("smog") occur (i.e., metropolitan areas in non-attainment with the ozone NAAQS (National Ambient Air Quality Standard)), not NOx.

[boosted475]

so i guess the claims on the commercials are not true

[wxman]

Originally Posted by boosted475

so i guess the claims on the commercials are not true

Depends on what it's compared to. Compared against the gasoline versions of the same vehicle (VW Jetta)...


http://www.arb.ca.gov/msprog/onroad/..._u2_diesel.pdf (ULEV II Jetta TDI)

http://www.arb.ca.gov/msprog/onroad/...200_2d0_u2.pdf (ULEV II Jetta 2.0T)

http://www.arb.ca.gov/msprog/onroad/...203_2d0_pz.pdf (PZEV II Jetta 2.0T)

(Grams/mile @ UL)

Emission.................VW Jetta TDI............Jetta 2.0L U2..........Jetta 2.0L PZ

NMHC/NMOG.............0.014........................0.02 7.........................0.004
CO...........................0.5.................. .........0.2.............................0.5
CO @ 20*F................----...........................2.9.................... ........2.4
NOx..........................0.04................. ........0.03...........................0.02
Highway NOx..............0.03...........................0. 01...........................0.01
PM...........................0.001................ ..........----..........................----
US06 HC+NOx............0.13...........................0 .03..........................0.01
US06 CO..................0.02.......................... ..4.4............................1.0
SC03 HC+NOx............0.12...........................0 .04..........................0.01
SC03 CO..................0.02.......................... ..1.5............................0.7
VEH. EVAP..............-----...........................0.0066................. ......0.0051

(not including evaporative emissions in the fuel supply chain)


Again, lower NOx emissions do not necessarily offset the higher HC (NMOG/NMHC) emissions, in my opinion.