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BMW M3 Competition Package – Click above for high-res image gallery

Stop-start technology has been available on numerous European automobiles for some time, and, according to Hybrid Cars, the fuel-saving tech is projected to be offered on up to 42 percent of vehicles in the U.S. by 2016. However, there are virtually no incentives pushing automakers to equip U.S.-bound models with auto stop-start, and there is one regulatory reason for them not to focus on offering this option.

The problem is that the EPA's current testing methods don't accurately assess the real-world fuel-saving benefits of stop-start technology, which shuts the engine off when the vehicle is stopped. The EPA only has limited idle time built into their fuel use tests, which means that most models equipped with start-stop get absolutely no bump in their official fuel economy ratings. Without any sort of official support, automakers see no boost in CAFE numbers for their start-stop vehicles. Currently, only three non-hybrid vehicles sold in the U.S. – the BMW M3, the Porsche Cayenne and Porsche Panamera – feature stop-start technology.

The lack of incentives, according to John Gartner, an analyst at Pike Research, will likely keep most automakers from equipping U.S. models with stop-start tech. However, Gartner claims that most American buyers would "embrace vehicles that don't burn fuel when stopped" if they were available.


  • BMW M3 Competition Package (02/2010)
  • BMW M3 Competition Package (02/2010)
  • BMW M3 Competition Package (02/2010)
  • BMW M3 Competition Package (02/2010)
  • BMW M3 Competition Package (02/2010)
  • BMW M3 Competition Package (02/2010)
  • BMW M3 Competition Package (02/2010)
  • BMW M3 Competition Package (02/2010)


[Source: Hybrid Cars]


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    • 1 Second Ago
  • 21 Comments
      uncle_sam
      • 4 Years Ago
      German CEOs say Mericans give a crap on start stop. They want to feel the engine rumble at a stop light and that those suv lovers don't care bout gas consumption anyways. Even in europe they tried to block this technology. cars with start stop (even with clutch and the ability to coast with engine off) were not advertised. the official garages and workshops were not instructed how to handle the technology. sadly you have to force them...
      Michael Taylor
      • 4 Years Ago
      Okay, this is kinda-sorta related. I live in Japan. I test drove a Honda Fit Hybrid with start/stop. It was a nice experience. When taking off again after the engine had stopped the starter motor did not restart the engine instead, the engine puttered back to life "on its own" in about a second. I just got a Daihatsu Move here with Idle Stop and once the motor stops and you release the brake, the starter motor turns over the motor and it's very loud and very annoying. I mention this just to point out that all Start-Stop technology is not created equal. Buyer beware!!!
        Nick
        • 4 Years Ago
        @Michael Taylor
        Yep. I drove the Smart ForTwo, and the start-stop was extremely annoying. I had to turn off the feature, even though I am a die hard clean tech supporter!
          Kai F. Lahmann
          • 4 Years Ago
          @Nick
          Is there anything not loud on the "wheelchair with roof"?
      JakeY
      • 4 Years Ago
      The UDDS (EPA city cycle) has a total of 259 seconds of idle time (0mph) out of 1370 seconds of testing. That's 18.9% of the test. I counted about 10 different parts of the cycle with ~10 seconds or more of idle, and out of that 5 parts have more than 25 seconds of idle. I think that's more than reasonable to simulate a typical stop sign and traffic light situation. The Euro urban cycle (the euro equivalent to our city cycle) has 64 seconds of idle time out of 196 seconds of testing. That's 32.7% of the test. So more that the UDDS by 13.8%. The cycle has 4 sections of idle time (if you count start and finish), each middle section 22 seconds. The epa site has all the details of all the relevant cycles (including the Euro cycle). http://www.epa.gov/nvfel/testing/dynamometer.htm If the EPA city test is adjusted to further to favor start-stop conditions, all that will do is bias the test even more toward hybrids and plug-ins (because they do the best in start-stop) and people already complain that the current test is too easy on them. The Euro cycle itself is already too lenient even for normal vehicles.
        Kai F. Lahmann
        • 4 Years Ago
        @JakeY
        The problem about start-stop: It doesn't have an effect on the fuel per mile; only on the fuel per time...
        Rotation
        • 4 Years Ago
        @JakeY
        Yeah, I don't get it. There is enough city cycle time in the testing for Porsche to put start-stop on the Panamera and have it default to on (it defaults to off in some countries).
          JakeY
          • 4 Years Ago
          @Rotation
          Reading the original article I think it has more to do with CAFE credits. The automakers want extra credits like they can get for adding E85 support. Also boost they get from start-stop in the EPA testing is so small that it might not even add 1 mpg to the city rating. Part of that has to do with the bad granularity and non-linearity of mpg (saving 1 mpg at 25mpg is different from saving 1mpg at 50mpg) vs liters/100km, but for the most part it's because start stop itself doesn't really net that big of an improvement. The Euro cycle currently gives 2-3x the idle time of the EPA test if you count both city/highway, which would boost start-stop's significance. However, if they bias the test this way, it'll make the EPA test even less "realistic" for hybrids and plug-ins, and lots of naysayers already like to say the EPA test needs to be made harder for them. IMO, the EPA test shouldn't be made to favor any technology, but should be made to get as close as possible to the average driving profile of an American.
      savagemike
      • 4 Years Ago
      I thought the new kia rio was going to have it as an option in the states??? I am quite curious to see what the cost of the option is/ what percentage of people choose it / and what real-world reports are of usage are like. I hope it is available across the range for a reasonable cost and is not locked into some special 'eco' only model, or only in the highest-end model or something.
      Yespage
      • 4 Years Ago
      The Start/Stop in my 2000 Honda Insight is nice. The mileage it gets going up a steep hill (~25 mpg) is outrageously fantastic! Start/Stop is one of the most overly hyped parts of a hybrid. A car that can start/stop, but only gets 30 mpg isn't a very pro-environment car. Car manufacturers shouldn't gain much of anything from start/stop as far CAFE is concerned.
      tantareanujellob
      • 4 Years Ago
      Talk about making a mountain out of a mole hill. THIS IS NOT NEWS
        Marcopolo
        • 4 Years Ago
        @tantareanujellob
        You appear to be swimming against the tide, but I agree! firstly this is very old news, secondly who cares about some very trivial,but complicated technology to improve by a tiny margin the life of a rapidly obsolete technology? No matter how the ICE is tweaked, it's destiny is doomed. this is like trying to improve analog mobile phone technology 2%.
      • 11 Months Ago
      The new BMW 528i also features Stop-start technology. I just rented one last week. It shows "Efficient Dynamics" at the bottom of the RPM gauge
      lne937s
      • 4 Years Ago
      Well, the EPA could add more idle time the the City portion of fuel economy testing, making it harder for cars without start-stop to meet fuel economy standards... However, I think the automakers want some sort of credit. Really, we should be removing all the credits (including the E85 credit) from CAFE and make it just about fuel economy. It also makes you wonder how inefficient our cars would be without government intervention.
      GR
      • 4 Years Ago
      Hey ABG, any comment from the EPA re: why they don't factor this in more or if they plan to address this in the future? It'd be nice to have a statement from them on this topic, rather than just the fact that they don't factor in start/stop technology in their testing.
      • 4 Years Ago
      I drive a Saturn Vue with GM's belt assisted starter system (BAS). The BAS system uses the alternator/motor to handle start stop. It was a little disconcerting at first. Its usually not a good thing if your car dies at a traffic light! Now it seems strange to drive a car that doesn't have turn off when you stop. The start stop has operated flawlessly for me. No start/stop noises or vibrations and the engine is always spun up well before I can move my foot from brake to gas pedal. The vehicle is not a pure start stop as It also uses the alternator/motor for boost on aceleration and includes low rolling resistance tires. DOE rates the combined fuel economy at 28 with BAS and 22 without BAS. I've averaged 29mpg over the last 83k miles and like the system.
      Nick
      • 4 Years Ago
      Think of of much gas start-stop can save in congested cities!!!!! In L.A., millions of cars are idling for HOURS!
      John R
      • 2 Years Ago
      I have problems believing the author's claims. Because even if it doesn't help their CAFE numbers, start-stop technology doesn't cost much to the automaker and can be a big selling point! This is something a car-maker can tout in their advertising. Customers will think they're getting the latest technology which will save them money - which is basically true.
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