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So, the real moral here is that Volkswagen took advantage of the fact that our emission standards basically trust the cars own on board diagnostics to determine
by abakker 11y ago
So, the real moral here is that Volkswagen took advantage of the fact that our emission standards basically trust the cars own on board diagnostics to determine if they pass emissions...
CA, at least, uses the BAR-OIS inspection for diesel cars, coupled with a "visual inspection" to make sure that the car does not produce visual pollutants. Effectively, this means that the software reads whether the car is passing from the OBD-II port in the car, and then, as long as the car has the necessary parts (Exhaust recirculator, catalytic convertor, etc) then it passes.
It would not surprise me to find out that more than just VW have these kind of issues. Effectively, we don't actually verify with any instrumentation whether the emissions are within spec.
Sure, VW may have duped the system on purpose, but, the fact that this has gone on for years has to weigh in a bit on a critical mind. Our tests don't work very well if this stuff can go on this long.
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Of course, it is also trivial to find an inspection location that will pass almost any diesel vehicle, if you know where to look. For any interested parties, try googling "diesel exhaust delete" or some similar query for any number of Ford f-350s, Ram 2500s or any other large turbo diesels. This basically consists of taking a saw, and cutting out the EGR, and some other flow restricting parts of the exhaust to increase exhaust flow, typically done in combination with a chip/turbo map.
The results can be significant. A person I know got a fairly significant bump in both power and MPG at the expense of needing to carefully plan how to pass emissions tests. The main question that weighs in is whether it is better to pass emissions and get 13-15mpg, or to fail emissions technically, but get 24-26Mpg with diesel. Those are real numbers with a 2008 Ram 2500.
I think this VW thing should spark a larger conversation about how we measure emissions in the first place, and what cost the emissions passing imposes.
- abakker 11y agoReplying to my own post to clarify my position: I'm not defending VW's actions. I'm questioning whereto our emissions testing regimen is good enough if this kind of stuff gets by for so long.
- noipv4 11y agoI think you mean the Diesel Particulate Filter delete. http://news.pickuptrucks.com/2013/01/epa-says-dont-touch-paticulate-filter.html http://news.pickuptrucks.com/2013/01/epa-says-dont-touch-pat...
- abakker 11y agoThat is certainly one part of it, though many people go significantly further. frequently, this involves simply sawing off the whole exhaust system and having a local muffler shop fab a new set of pipes and mufflers for you. The truck that my friend has is a ram 2500, with a chip/tune and the exhaust removed, it dynos at about 490HP/1100 ft-lbs of torque, and still achieves ~25mpg highway. The downside is that there is an unknown emissions toll for doing that modification. Again, I have to wonder though, at almost 10mpg better, is the reduced emissions actually logical? i.e. do the emissions reduction systems really make up for needing to burn additional fuel to do the same work?
- hapless 11y agoWhether it's "logical" depends on your goals. If you value public health more than fuel efficiency, then yes, emissions controls are a logical choice.
- vonmoltke 11y agoabakker was questioning how much the increased emissions per unit fuel was offset by the reduction in fuel required for a given distance. When calculating vehicle emissions per distance traveled, those counteract each other.
- abakker 11y agowell, thats what I'm getting at. By getting 10mpg better, do you produce fewer total emissions than if you had the emissions controls in place, but burned more fuel? I imagine than there are many possible solutions where it makes sense to use strict emissions controls at the cost of fuel consumption, but there are also others where the increase in mileage would reduce total emissions further than the emissions controls would. rough estimate. on a 25 gallon tank of diesel, with emissions controls in place, the truck goes 350 miles. on that same tank, the truck goes 625 miles with the emissions removed. so, to go 625 miles with the exhaust controls in place would use ~44 gallons of fuel vs 25. Is that actually a net environmental benefit? My gut tells me that the environmental costs of refining, transporting and burning the extra fuel are higher than the marginally higher emissions in the unrestricted truck. I don't expect those numbers would work out the same in all vehicles or cases though. I think public health and fuel economy go hand in hand. the total environmental costs of petroleum are much higher than the emissions that come out of cars. reducing demand through greater fuel economy should be factored in to the overall emissions equations.
- tzs 11y agoThe VW cheat did not merely lie about what the car reported via the diagnostics port. It detected dynamometer testing for EPA certification and altered the engine calibration to produce compliant emissions.