Conduce Chile

Apuesto a que en Chile van a salir diciendo que cumplen todas las normas chilenas.

De lo que lei, es que existen procedimientos estandar para hacer la medicion y eso incluye un regimen especifico de RPM para lo cual la ECU cambiaba automaticamente los parametros para cumplir.

Id like to add to this discussion. I’m a diesel engine performance engineer.

Its important to note that NOx emissions are a product of heat and pressure that are present when combustion is efficient. In simple terms if you atomize fuel well, and inject at optimum timing for efficiency (per the thermodynamic cycle) you get NOx. Reducing NOx is very difficult and pretty much ends up hurting fuel economy one way or another. In the biz we call this the NOx Vs BSFC trade off. BSFC stands for Brake Specific Fuel Consumption, and is used to express fuel efficiency of an engine. It’s well understood by the engineers involved. The best path to control NOx and provide a good customer experience (power and fuel economy) is with careful engineering and often aftertreatment. These things often add cost to the product. However if you ignore the legal requirement for controlling NOx you can - and will - be at a huge advantage compared to the competition. Fuel economy will be improved, and or product cost reduced (by not using the urea dosing SCR system). Both of which make a big difference to sales.

Americans have wanted 40mpg + diesels like Europe enjoys for some time, however Europe doesn’t have the same strict NOx standards employed by the US. You can argue about “why” all day but the US and California specifically have had to deal with smog caused by NOx and Hydrocarbons and local climate (sunshine and a city surrounded by mountains). The EPA and CARB rules are important at limiting smog and making a level playing field for those wishing to sell cars and engines in the US market.

These rules are the reason why you cant buy Euro zone diesels in the US that get the same 40 to 50mpg+ fuel economy. To engineer them for the US market means hurting that fuel economy, and adding cost in aftertreatment. Sales would be poor, profit margins slim, and most car companies rightly figure it would be a money losing prospect once the engineering dollars are accounted for.

VW has been the sales leader in this arena and I suspect many other manufacturers have been quietly wondering how the f*$k they have been able to do this. The answer - in a nutshell is cheating. They never would have been able to sell these cars with the 40+ mpg ratings, without SCR aftertreatment - at affordable prices - without cheating. It will be interesting to see if other VAG products have employed similar cheats to skirt the regulatory requirements.

The cheating was clever, by running an MPG friendly calibration during normal driving, without urea dosing SCR. Then when the specific loads and speeds of an EPA engine emissions test are detected, to run on a different calibration map and change injection parameters to pass the test. If the car ran on the “clean” map all the time it would be apparent that the driving experience and customer value (fuel economy and power) would be significantly impacted. We know this because otherwise VW wouldn’t have cheated, the cars would be driving on the “clean” maps all the time. It obviously makes a big difference. Without sophisticated testing and an eye for detail this never would have been discovered. Local and state in chassis testing is not sophisticated enough. Generally on newer vehicles local testing requires having no OBDII codes and the OEM certificate plus a visual inspection.

My point is that this isnt really just about emissions, this is about a level playing field for manufacturers trying to engineer cars with good fuel economy and lowest cost. By cheating they were able to put a car on the market that stood out from anything the competition could do.

VW have admitted fault, presumably because the evidence is in all the cars and by coming forward they hope the EPA may go easier on them. The fines and penalties have yet to be decided. Its possible that a recall may be required, and that while usually voluntary the EPA may try to figure ways of making people take their car in (limiting registrations etc..). If left up to the customer they may choose not to have the recall work done (electing instead to continue driving with better fuel economy and higher invisible odorless NOx emissions that cause smog). This could be quite the interesting situation, get your EPA approved popcorn ready.

Pero con dinero todo se arregla, van a pagar las multas llamaran a un recall y en 9 meses más ya nadie se acordará


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