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Re: Volkswagen and the "smog defeat" devices

Posted: Thu Sep 24, 2015 9:18 pm
by asiab3
If I recall correctly, BMW was able to manufacture a diesel sedan without urea exhaust injection and meet US standards. Now to see if they're cheating too, I suppose?

Remember that OBD2 cars aren't sniffed on dynos anymore, at least not in CA where we have Too Many People and tests that are strict and laws that help, and are important. Now the programming gets more interesting, because the OBD memory is accessed, and sensors are read in real time at idle.

Big rig (Volvo maybe?) engines used to (and maybe still do) foul up on the road once the software has shown that the truck is up to consistent operating speed for longer than a few minutes. I think this was in the interest of fuel economy.

Robbie

Re: Volkswagen and the "smog defeat" devices

Posted: Mon Sep 28, 2015 6:31 am
by Amskeptic
asiab3 wrote:If I recall correctly, BMW was able to manufacture a diesel sedan without urea exhaust injection and meet US standards. Now to see if they're cheating too, I suppose?

Remember that OBD2 cars aren't sniffed on dynos anymore, at least not in CA where we have Too Many People and tests that are strict and laws that help, and are important. Now the programming gets more interesting, because the OBD memory is accessed, and sensors are read in real time at idle.

Big rig (Volvo maybe?) engines used to (and maybe still do) foul up on the road once the software has shown that the truck is up to consistent operating speed for longer than a few minutes. I think this was in the interest of fuel economy.

Robbie
I am most-interested in the personal side of this imbroglio, the corporate culture, the contempt for regulations, the spin being imparted. I have read blog posts saying, "SEE? If you regulate businesses too much, they have to cheat!"
Colin

Re: Volkswagen and the "smog defeat" devices

Posted: Mon Sep 28, 2015 12:05 pm
by glasseye
Arrogance and lawlessness aside, what blows me away is the idea that they thought they could get away with it. :scratch: The only explanation I can come up with (so far) is that they're all doing it. It's SOP :bootyshake:
(Standard Operating Procedure)

Re: Volkswagen and the "smog defeat" devices

Posted: Mon Sep 28, 2015 3:06 pm
by jeb1978
VW did make a diesel that met emissions without using urea (or diesel exhaust fluid, as it's called in the USA).

The engine in the Jetta, Golf and Beetle used a NOx adsorber instead of SCR up until 2013 or 2014. Both technologies work to remove NOx emissions from the tailpipe, just in different ways. The NOx adsorber uses a catalyst that's like a sponge to absorb NOx emissions, SCR uses DEF sprayed into the exhaust to reduce NOx. I don't know if the Passat used a NOx adsorber; all the Passats I've seen use an SCR system.

The Cummins 6.7L diesel in the Dodge Ram 2500 and 3500 pickups from 2007 to 2013 uses a NOx adsorber system as well and does not require DEF.

There are tradeoffs in fuel economy and performance when using a NOx adsorber vs SCR, with SCR being the winner in both categories at the expense of having to carry DEF around and refill it every so often. The impending CAFE standards for fuel economy has forced all manufacturers that I know of using a NOx adsorber to switch to SCR.

Note that the NOx adsorber and SCR only reduce NOx emissions. The "black smoke" is particulate matter and is captured by a diesel particulate filter.... so your typical diesel engine today has two complete exhaust aftertreatment systems on it.

There's several solutions to diesel emissions regulations out there: exhaust gas recirculation, diesel particulate filters, diesel oxidation catalysts, NOx adsorbers, selectic catalytic reduction, etc. All the manufacturers use some combination of the above to meet emissions standards. Most (if not all) on highway diesel engines today have EGR, DOC, DPF and SCR. The standards for off highway diesel engines aren't quite as stringent as on highway (yet) so they may use less of the above, such as EGR, DOC, SCR or just DOC and SCR.

There's a huge balance at play here, generally what is good for emissions is not good for fuel economy and vice versa (you could add reliability and durability in that equation as well). You have to find a balance, but ultimately emissions wins as if you don't meet emissions, you don't sell anything, no matter how good your fuel economy, etc. is.

Volvo/Mack/Cat/Cummins/Detroit got their hand slapped by the EPA in the late 1990s as the EPA accused them of having two different electronic tables in the ECM, one for transient (stop and go) and one for steady state (cruise control). The EPA claimed that the transient table was in emissions compliance but that the steady state table was not. Ultimately, the engine manufactures settled with the EPA. No guilt was admitted and no further charges were pressed, but the engine manufacturers had to each pay a fine, release calibrations for existing engines that the EPA would approve, as well as the impending 2004 diesel emissions change due date was moved up to 2002. The agreement was called "The Consent Decree."

Re: Volkswagen and the "smog defeat" devices

Posted: Fri Oct 02, 2015 2:20 pm
by Amskeptic
jeb1978 wrote: No guilt was admitted and no further charges were pressed, but the engine manufacturers had to each pay a fine, release calibrations for existing engines that the EPA would approve, as well as the impending 2004 diesel emissions change due date was moved up to 2002. The agreement was called "The Consent Decree."
Interesting read . . . did you mean "adsorber" or "absorber"?
Colin

Re: Volkswagen and the "smog defeat" devices

Posted: Fri Oct 02, 2015 2:49 pm
by jeb1978
Adsorber. First time I heard that word I thought someone was joking, but it's real. This link goes into much, much, more detail if you're interested.

https://www.dieselnet.com/tech/cat_nox-trap.php

And "consent decree" isn't quite right, that's a generic term for an agreement. The basics of the case are at this link.

http://www.justice.gov/enrd/diesel-engines

Re: Volkswagen and the "smog defeat" devices

Posted: Sat Oct 03, 2015 8:13 am
by dingo
The EPA, like most regulatory agencies, strikes me as inherently weak, staffed by either politicos, or those who have been or will be in corporate positions..revolving door of backdoor handshakes

Re: Volkswagen and the "smog defeat" devices

Posted: Mon Oct 12, 2015 11:33 am
by Amskeptic
Mercedes, Honda, Mazda, Mitsubishi join Volkswagen in the diesel emissions scandal row

Saturday, 10 October 2015
Mumbai

It was revealed that Renault, Nissan, Hyundai, Citroen, Fiat, Volvo and Jeep were also involved in pumping out more NOx than permitted.
Representational image Representational image Getty Images
According to the Guardian reports, four other car companies have joined Volkswagen in the emissions scandal row. Mercedes-Benz, Honda, Mazda and Mitsubishi's diesel cars have been alleged to emit more pollution than in regulatory tests.

Reportedly, Honda models emit six times the regulatory limit of NOx pollution and other models emit 20 times the NOx pollution coming out of their exhaust pipes.

NOx pollution is believed to cause premature deaths and has also resulted in increase in health costs. Nick Molden whose company Emissions Analytics tested the cars told the Guardian that "the issue is a systematic one".

It was revealed that Renault, Nissan, Hyundai, Citroen, Fiat, Volvo and Jeep were also involved in pumping out more NOx than permitted.

Data from Emissions Analytics revealed that Mercedes-Benz cars emit 2.2 times more NOx than permitted. Honda, Hyundai and all the other cars' NOx emissions are alleged to be higher on the road than in the EU lab test.

According to the Guardian, Mercedes and Honda said they are supporting a tightening of regulations. In order to help strengthen regulatory and consumer confidence, Honda said they supported additional testing.

An emissions expert at Transport and Environment, Greg Archer told the Guardian that the new emissions analytics result prove that Volkswagen scandal is just the starting. "What we are seeing here is a diesel-gate that covers many different car models."

The only solution according to him is to conduct fresh tests on the road and verify it by an authority which is not biased or paid by the car company.

Last month, Volkswagen had been found to have flouted stringent US emission norms, by fitting a defect device that makes the engine function at a reduced capacity, thereby emitting lesser gases when the vehicle determines that it is being inspected. Otherwise in the real world, the defect device will turn off and will function at full capacity for a better performance.

Volkswagen had said that nearly 11 million cars worldwide have the defect device. Volkswagen Passenger Cars hds said that about 5 million cars have the cheating device, while Audi admitted that 2.1 million of its cars are affected, and 1.2 million Skodas have the device.
Skoda? Not Skoda . . . . !

Re: Volkswagen and the "smog defeat" devices

Posted: Mon Oct 12, 2015 1:35 pm
by tristessa
Amskeptic wrote:Skoda? Not Skoda . . . . !
The Škoda I drove in Finland last summer was a nice peppy little car, though it was bensiini not dieseli. About the size of an '80-'84 Jetta...