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When I last bought a VW (2008) I was concerned due to a clunking noise after first starting it up and driving a few miles; I called the VW service dept and they

• spydum 11y ago
  Perhaps the noise was poorly explained. What they describe is likely the Exhaust Gas Recirculation (EGR - https://en.wikipedia.org/wiki/Exhaust_gas_recirculation https://en.wikipedia.org/wiki/Exhaust_gas_recirculation ). This isn't a system to game emissions, it's an active component in real emissions reduction. Still I get your point: manufacturers are clearly going to optimize based on the measured metrics. How do we know those metrics are meaningful in the overall system.
  • s1lver 11y ago
    ERG is just a pipe from the exhaust to the intake with a valve. Compressing and carefully releasing would be much more complicated and very much a not normal way of lowering exhaust temperature to reduce emissions.
    • spydum 11y ago
      Yes, on second thought, they probably confused secondary air injection ( https://en.wikipedia.org/wiki/Secondary_air_injection https://en.wikipedia.org/wiki/Secondary_air_injection ) with EGR. It's very possible they were explaining secondary air, which doesn't compress exhaust gas, but does inject air into the exhaust gas to help burn more efficiently (not clear on the mechanism, I always thought it was a method to improve catalytic converter efficiency at startup).
      • jhallenworld 11y ago
        The usual failure mode is that it sounds like a loud vacuum cleaner for ~90 seconds after cold start up.. not sure about clunking.
        • Alupis 11y ago
          I owned an RX-8 which had an air pump (secondary air injection) which would come on for about 30 seconds on a cold start. When the pump started going out, it would make a metal grinding sound. Drove like that for a few years until it quit working, and didn't think anything of it until SMOG time - $600 for an air pump which works for ~30 seconds...
        • heywire 11y ago
          Exactly. Cheverolet Trailblazers are well known for this (I owned one and had to replace said air injector)
      • lutorm 11y ago
        I think the idea is that cold engines run rich, so injecting air into the exhaust gives the unburnt fuel a chance to combust in the exhaust pipe before getting to the catalyst. This is good for two reasons, first, it heats the catalyst up faster, which is good, and it also reduces the amount of unburned hydrocarbons.
• kaffeemitsahne 11y ago
  Just like sports, even stiffer fine and ruined reputation on being caught cheating.
  • nitrogen 11y ago
    Just like sports, even stiffer fine and ruined reputation on being caught cheating. Just like sports, companies will still cheat. When punishment doesn't work, the answer is rarely more punishment.
    • sbov 11y ago
      Caveat: if the punishment does not exceed the profit from cheating, it's not a punishment it's a cost of doing business.
      • swang 11y ago
        See: Johnson & Johnson w/ their drug risperdal: $2 billion in penalties... $30 billion in sales. http://www.nytimes.com/2015/09/17/opinion/nicholas-kristof-when-crime-pays-jjs-drug-risperdal.html http://www.nytimes.com/2015/09/17/opinion/nicholas-kristof-w...
        • refurb 11y ago
          That's a poor comparison. Not all of the $30B in sales were fraudulent. Actually, in order to come up with the $2B penalty, the gov't determines the number of fraudulent Rxs, then hits the manufacturer with triple damages (this is typical). J&J would have been better off financially had they never committed the fraud they did.
          • emn13 11y ago
            You need to account for the probability of being caught. It's quite likely to be significantly lower than 1/3, so they might still have come out ahead. Even if they're just breaking even, it's a kind of loan - they had the gain a long time ago, and pay the costs much later. If you're a risky business, that's potentially worth a lot, since investors might be hard to find. And if you account for that you need to account for the asymmetry of risk due to bankruptcy protections - even if the average payout is negative, fines are effectively capped at what the firm can pay, so the effective expected payout may still be positive. (Assuming those making this decision escape personal liability).
• CurtHagenlocher 11y ago
  There is a more charitable interpretation. When engines are colder, they burn less efficiently and produce "worse" emissions. A system that treats the warmup period differently than the steady-state of running a hot engine is potentially quite reasonable.
  • izacus 11y ago
    If you output those same emissions at a different time you haven't really done a lot for environment (except if they're cycled through catalyc converter or DPF filter which are usually less effective on cold start) - you're just gaming the system to get better eco ratings.
    • toomuchtodo 11y ago
      If you're recirculating exhaust back into the engine, you're able to attempt to reburn any fuel that wasn't burned on the first pass, while also exposing any emissions to higher temperatures on the second pass (higher temperatures = easier to break down when those emissions reach the emissions control system).
      • refurb 11y ago
        If you're recirculating exhaust back into the engine, you're able to attempt to reburn any fuel that wasn't burned on the first pass That's not what EGRs do. EGRs take exhaust, which is relatively inert (combustion having already taken place) and injects it into the combustion chamber to lower combustion temperatures. The reason you want low temperatures is that NOx (nitrogen oxides) form at high temperatures.
        • deleted 11y ago
          [deleted]
        • toomuchtodo 11y ago
          It appears I was mistaken! https://en.wikipedia.org/wiki/Exhaust_gas_recirculation https://en.wikipedia.org/wiki/Exhaust_gas_recirculation "In internal combustion engines, exhaust gas recirculation (EGR) is a nitrogen oxide (NOx) emissions reduction technique used in petrol/gasoline and diesel engines. EGR works by recirculating a portion of an engine's exhaust gas back to the engine cylinders. This dilutes the O2 in the incoming air stream and provides gases inert to combustion to act as absorbents of combustion heat to reduce peak in-cylinder temperatures. NOx is produced in a narrow band of high cylinder temperatures and pressures. In a gasoline engine, this inert exhaust displaces the amount of combustible matter in the cylinder. In a diesel engine, the exhaust gas replaces some of the excess oxygen in the pre-combustion mixture.[1] Because NOx forms primarily when a mixture of nitrogen and oxygen is subjected to high temperature, the lower combustion chamber temperatures caused by EGR reduces the amount of NOx the combustion generates (though at some loss of engine efficiency).[2] Gasses re-introduced from EGR systems will also contain near equilibrium concentrations of NOx and CO; the small fraction initially within the combustion chamber inhibits the total net production of these and other pollutants when sampled on a time average. Most modern engines now require exhaust gas recirculation to meet emissions standards."
• Havoc 11y ago
  >the emissions guidelines were being gamed by manufacturers Not necessarily gamed - the measuring just needs to factor it in. e.g. (Rather anecdotal) I know there are cars programmed to capture emissions in a filter & then automatically clear that when the car reaches high speeds (freeway). Makes sense in a way...you'd rather have the car expelling the crap on the freeway than city center. That mechanism is apparently a big problem here - I live in a place where the cars never reach freeway speed so they keep clogging (so I'm told).
  • ibarrajo 11y ago
    I believe you mean the EVAP system where excess gasoline vapor is condensed in a charcoal canister, this canister is purged generally in a freeway with a high engine vacuum going on. the highest vacuum is achieved when you engine brake
• brobinson 11y ago
  Some models of the Yamaha R1 have an intentional flat spot in their fuel maps which happens to be right at the spot where testing happens, too. In a similar vein, the Aprilia RSV4 kind of cheats at noise testing: in neutral, there is a baffle which flips down to dampen the exhaust note a bit. :)
  • vesrah 11y ago
    Almost all supersport bikes coming into the US utilize both of these strategies. :) I own a Ducati 999 that was lemonlawed because it would stall at stop lights. Super common and happened because of how lean the bikes had to run to pass US emissions.
    • brobinson 11y ago
      Google said "random stalls" were kind of endemic to Ducatis. :P Didn't know it was related to the fuel mapping! I had a 1098 which would occasionally (maybe once per month) randomly stall at 0% throttle when braking to a stop. I had a full Termignoni system + race ECU, though. California doesn't do emissions testing on bikes, surprisingly! I had to put a Power Commander on my R1 because of the aforementioned lean spot. The engine would "chug" at about 37mph (5.2k rpm in 1st gear), which unfortunately happened to be a very common cruising speed. Google showed lots of complaints for other years as well.
      • toomuchtodo 11y ago
        I can assure you that the engine on the R1 doesn't chug along at sport bike speeds though ;)
        • brobinson 11y ago
          Yes, certainly not. :) https://www.youtube.com/watch?v=HSsP-itS8qI https://www.youtube.com/watch?v=HSsP-itS8qI I commuted to work in San Francisco on literbikes, but on weekends I would head south and open them up.
• Evolved 11y ago
  Just because they used various tools to attempt to meet EPA standards doesn't mean any or all of those tools are illegal. What you're describing sounds like either a smog pump and/or a charcoal canister. Both are legal and widely used means of controlling emissions. The emissions guidelines, in your case, likely weren't being "gamed" so much as the manufacturers were just coming up with innovative and cheap ways of reducing emissions. Start/stop features on some newer cars are a way of doing this but this doesn't sound like someone "gaming" the system. If you're not very automotive savvy then you may have misunderstood what the technician was explaining or the logic/purpose behind the system. What VW did though is completely different with regards to the software although not necessarily illegal until we have all the facts. Based on what the article says, it sounds like they developed a special "emissions mode" which went outside the normal operating parameters with the ultimate goal of reducing the emissions. That in and of itself is not illegal since it passed emissions that way. The illegal part probably comes from when it switch back into normal mode where it never would have passed emissions that way. We can assume for one reason or another that the "emissions mode" is unsustainable for regular driving (for one reason or another) which is why it was only used when absolutely necessary to pass emissions.
  • developer1 11y ago
    Huh? They disable "emissions mode" during all driving either because a) it was bad for sales - perhaps one is unable to reach race car speeds in < 10 seconds; or b) they purposely chose not to build a compliant emissions reduction system and covered it up by specifically making the cars pass only during examination. There is no apology to be made for them. Manufacturers are required to build sustainable systems, it's not optional. Unless the initial facts turn out to be wrong, this is clearly inexcusable.
    • Evolved 11y ago
      I see what part of what I said made you confused. The "unsustainable" part of what I meant was that it caused some sort of undesired effect be it affecting performance or causing accelerated wear on components that could be costly to replace under warranty or some other condition. Either way, I agree, VW did this intentionally and there is no question as to their motives behind it. I'm sure they'll be severely punished for it.
• Sanddancer 11y ago
  That sounds more like a Diesel Particulate Filter and regenerator ( https://en.wikipedia.org/wiki/Diesel_particulate_filter#Regeneration https://en.wikipedia.org/wiki/Diesel_particulate_filter#Rege... ), which is pretty much the opposite of gaming. To keep the black clouds of soot that have sullied the name of diesel from forming, most modern diesels are designed to capture the soot until the engine gets warm enough to burn off the soot, at which point said soot is passed back through the engine and incinerated. Or, there's some mix of heater and catalyst to burn off the soot in the regenerator itself. You're basically holding onto the waste until you can efficiently deal with it in an environmentally clean manner.