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That explains why people buy a Camry or an Accord instead of a BMW, Audi or Mercedes. They are cheap. People like Ferrari and Porsche also but they end up buying a Miata or S2000. It all has to do with bang for the buck. I would imagine not having driven one that you can have as much fun in a Honda S2000 as a Porsche 911.
vs
almost NONE (on a long downhill grade) in gear.
As a practical safety matter, I would not let an engine coast several miles in neutral down a LONG grade. In fact doing so in some states can be against the law.
I did a 600 plus (mapquest sez 624 miles) mile trip from downtown Durango CO to (on the strip) Las Vegas NV (LONG downhil descent) but filled up at 584 miles (out in the middle of seemingly NOWHERE) at app the 6 hour of travel mark with 12.1 gal. I had estimated (before the actual figures) to get several (3 actually) mpg LESS than what I actually got. WOW !!!! I often wonder what a Toyota Prius would get given the same dynamics.
28 May 2006
VW diesel model sales Jan-Apr 2006.
The Detroit Free Press reports that Volkswagen of America will drop the diesel versions of the Jetta, Golf and Beetle models from its USA line-up for the 2007 model year due to their inability to meet the new, incoming stricter emissions standards nationwide.
Currently, VW only sells its diesels in states covered by USA EPA emissions requirements; the diesels do not meet the tougher California standards, and are not sold in California, Massachusetts, Maine, New York or Vermont. With the phase-in of the EPA Tier 2 standards that comes fully into effect this year, the USA and the California standards are converging, however.
USA EPA Tier 2 and CA LEV II Standards (g/mi)
Category 50,000 miles 120,000 miles
NOx PM CO HCHO NOx PM CO HCHO
EPA Bin 8 0.14 0.02 3.4 0.015 0.20 0.02 4.2 0.018
EPA Bin 5 0.05 0.01 3.4 0.015 0.07 0.01 4.2 0.018
CA LEV 0.05 0.01 3.4 0.015 0.07 0.01 4.2 0.018
CA ULEV 0.05 0.01 1.7 0.008 0.07 0.01 2.1 0.011
VW will offer a diesel version of its Touareg SUV in 2007, although monthly sales of the current diesel Touareg model have so far been in the single-digit range. VW, according to the Free Press report, also plans to build extra model year 2006 diesel Jettas, which it hopes to sell well into next year. A new “50-state” diesel Jetta should be available for the 2008 model year.
Diesels as a component of VW’s sales rose from 12% in 2003 and 2004, to 14% in 2005, and to 22.7% for the first four months of 2006. (Earlier post.)
“They are becoming a significant part of our business, so it’s disappointing,” [VW spokesman Steve] Keyes said. “If diesels continue to contribute 20%-22% of our sales, this has some significant impact on us.”
The removal of the VW diesel models from the MY2007 lineup will leave only DaimlerChrysler with a new diesel passenger car to sell into the USA (E320 BLUETEC). (Earlier post.)
=========================================================
Honda recently announced it would introduce a Tier 2 Bin 5 compliant diesel in the US within the next three years, and has patented a new plasma-assisted catalytic NOx reduction system that may factor into its plans. (Earlier post).
Evidently burning 37% MORE fuel (to get the same job done) is better for the environment than burning LESS FUEL.
Evidently the EPA's do not give as much credence or see it as a non problem the dependence on foreign oil CRISIS as other parts of the governments!
Or the reality might be that VWA is not as in bed with the politicos as either the domestic automakers and/or Toyota or Honda.
Before leaving on a 300 mile trip to visit my mother, I tightened the alternator belt. In doing so I unplugged the alternator cable to get access. FORGOT to plug the alternator back in!
Drove my merry way to Saratoga NY blasting the stero. Spent three days there but didnt drive the car. When it came time to leave, the battery was dead. This greatly puzzled me because I liked to keep that car in tip top condition. Got a jump from Triple A and started the trip home. It was getting dark as I left so as I got on the freeway I turned the lights on. (It was January 1st and about 12 degrees) Nothing. Im thinking about this when the lights go on and I realize what I did. Pulled over and left the engine on. If I shut the engine off I cant restart it. I can reach the alternator plug OK but do I want to plug it in with the engine running? Yes Im getting lazy in my old age. When I do so there are visual and audible sparks. Well Looks like I just fried the alternator! Nope the lights work! And it worked for the rest of the five years I owned the car!
Mileage particulars for the 240D (manual transmission) 28 mpg around town and 32 on the highway. I should point out I bought the car twelve years old with 105k on it. The beautiful thing was it had a 20 gallon diesel tank which gave a highway range of over 600 miles.
There are almost no diesel engine vehicles in Japan, where they are widely considered unfriendly to the environment. In Europe, however, diesel engines are regarded as environment-friendly because they are more fuel-efficient than gasoline engines and so discharge less carbon dioxide.
The new diesel engine under development by Honda will be able to "clear tough emission regulations in the United States and curb the generation of nitrogen oxide and particulate matter to the comparable level of gasoline engines," Fukui said.
Honda, which already sells diesel engine vehicles in Europe, will install the engine in vehicles for the Japanese market as well as the United States.
Fukui also said the automaker will step up marketing in India in a bid to take advantage of the nation's strong growth potential.
Copyright 2006, Kyodo News International, Tokyo
Volvo C70 D5
• First diesel engine in the C70
• 180 hp and 350 Nm
• Every fifth C70 a diesel
• D5 a viable alternative to the T5
• Particulate filter standard
For detailed info:
http://www.autospectator.com/modules/news/article.php?storyid=4454
your CRD owners manual might mention something about "zero fuel" being used in the conditions we are discussing. many vehicle owners manuals do reference this simple fuel-conserving measure that has been in cars for 20 years or more. cheers & happy dieseling to you !
My wife has a 1998 Chrysler Concorde and when coasting, less fuel is used, but the engine keeps running and does not stop using fuel. It will use less fuel. When I step on the gas, the engine does not restart.
In the scenario you propose, such might apply to a Prius. For non-hybrids, it is just not so. There is always fuel flow to the engine.
Try going down a hill in neutral with the engine running. Does it stop? No, it runs at idle and is therefore using fuel. Same or similar applies when coasting. The engine continues to run and uses fuel.
Your proposition that an engine uses "zero" fuel while coasting is totally in error, unless you are driving a Prius.
Have any of you ever tried the trick where you let a car (manual) roll backward down hill (with the with the transmission in reverse and the clutch pushed in and the egnition in the "ON" position) and Pop out the clutch and push it back in really fast while and hitting the gas at the same time. The engine starts with out the having someone jump you off. It really a cool way to start your car.
The whole point of that was that if you have ever messed it up and didn't it the gas fast enough you know just how strong that compression strock is. You will be jerked to a stop. This is the same principle that allowed me to do engine breaking in my manual truck. When coming to a stop down shift and let off the clutch with your foot off the gas and the car will slow rather quickly.
Just because your car is reading 199mpg doesn't mean that their is no fuel going to the engine it just means that there is so little that it can't acuaratly read anymore. As the pervious person stated your car would have to float all the valves and let the engine free spin to do that.
In some new GM cars there is a feature that turns off 4 cylinders when at highway speeds. This is similar to what you are talking about no gas goes to the cylinders, but they float the valves, the exaust valves is left open during the compression stroke.
A regualar IC gets fuel all the time, even if the car is rolling down hill, with your foot off the gas, in N, with a strong wind at your back. If you don't believe me on the way home when rolling down hill shift into N and see what happens. If your RPM fall to 0 your are right and congratulations, but if the RPM hold at 1500 or what ever then your car gets gas all the time like everyother car on the road. If it didn't get gas it would not take long for the compression stroke to stop you even goign down hill.
When rolling down a hill in gear (coasting), and when I do a reset, the economy/mpg reading goes to 99 mpg, but the engine is still running and the tachometer shows rpms in around 1500 to 1700 (depending on the speed). If I shift into neutral, the rpms drop to base idle speed of 750 rpm, thus in either case the engine keeps running and uses fuel. So Goodcrd's points are valid. If you are driving a Prius, then the engine will probably shut down while coasting down a hill while the electric motors help to maintain momentum.
As I have stated earlier, the engine continues to consume fuel, but a reduced rate and as Goodcrd has pointed out, that rate is so low that the mileage computer does not give you a correct reading.
Again this is VERY easy to verify or put to rest by hooking up a VAG.com and laptop computer and reading the graphic results.
For a more technical description for those interested do a search on www.tdiclub.com.
Ask several dealers or reputable mechanics and see what they say.
really, this basic premise of fuel-injection operation is such old news, old technology. for decades ECMs have been programmed to use zero fuel when foot is off the go-pedal. there is nothing new here, except new people keep showing up who are confused about basics of engine/vehicle operation.
the dudes who asked about the valve operation in this no-fuel-foot-off-go-pedal-mode are asking the interesting questions though...
asking a reputable mechanic is a good idea for those who don't already "know" the right answer - like me & winter2 - even though our answers are opposite!
a google search of owners manuals online might yield a few hundred vehicle owners manuals which state the facts about zero-fuel being used while going downhill in gear, as long as speed is great enough. my 1989 IROC owners manual mentioned it! if GM figured it out during the 1980s, maybe D-C has figured it out by now too for the CRD !
The answer is that you are wrong!!!!!
On the vast majority of injected engines, there is still fuel consumption. The amount of fuel injected is smaller than usual producing a very lean mixture. The injector pulses are very short too. There is near fuel shut off, but a little fuel is still injected and it is just enough to keep the engine barely running. This applies to GM, Ford, Chrysler, Toyota (except Prius like hybrids), Nissan, etc.
Hybrids work."
Well, that technical analysis is about on par with the rest of this discussion.
"What's wrong" is that I go to this forum to view discussions of hybrid vs. diesel, which to me means their technical comparison and general efficiency, along with reasoning as to why one is better than the other. I don't like having to scroll down past postings that have nothing to do with the forum.
Cost is relevant and on topic; geopolitics is not. In my opinion, of course.
Holy diesel fumes, batman!
instead of just typing the same things back and forth to each other, let's try to actually document our claims! i've already mentioned "1989 IROC owners manual", but we can't find that online.
i'm never sure if i can post URLs here or not.
google search of "fuel injection zero downhill" yields results from a dude who hacked/disassembled a GM ECM. I suppose you won't believe him either so maybe a little more googling will result in more docs to bolster either your or my position. here's what the disassembly/hacker dude wrote at "customefis" web site in 2002:
DECEL FUEL CUTOFF ? Decel fuel cuttoff means exactly that. When you
take your foot off the gas pedal going downhill or decelerating
quickly, the ECM will cut off the fuel entirely. The difference
between this term and the next one, DECEL FUEL ENLEANMENT, is that
some fuel is allowed to reach the engine during DECEL Enleanment. As
to when one or the other occurs, I don't know. I do know that on my
TPI system, I noticed a lunge from the engine right around 1500 RPM,
so I think this is where the DECEL fuel enleanment takes over from the
DECEL FUEL CUTOFF. The lunge was significant and could easily cause
you to run into the something if you weren't expecting it. I also
believe a speed sensor is required for these two modes to operate
period. So this is another reason to have a speed sensor.
DECEL FUEL ENLEANMENT ? See Decel Fuel Cutoff above.
****
so again we have something else in addition to my mere recollection of my five Z28 owners manuals - which backs my allegation (FACT!) that zero-fuel-used-downhill really means zero-fuel-used-downhill.
maybe next i will arrange to quote an engineer from GM technical assistance center or some inventor of fuel injection! (woody allen movie fans remember the scene in _annie hall_ where some guy misattributes Marshall Mcluhan in the movie line?)
The fact of the matter is this is where the other TDI oem's will be going, if they have not already gone.
I don't see that much difference between the 2 camps here.
Does it really matter if let's say over a 10 mile stretch downhill, the car uses 0 fuel, or 100ml of fuel.
Yes, IF you have long downhills you will experience BETTER AVERAGE MPG OVERALL. I posted my projected (44/45 mpg) vs actual (48.26 mpg) on a trip with a very long downhill run (Durango, CO 6,550 ft to Las Vegas, NV 2,100 ft). So over the length of the trip (584 miles) I got up to 51 MORE miles. This represents about 1 gal of savings. Or 8.3%.
NO, if you either do not track those things or care.
So dial in your option and the appropriate consequence will be felt !!
Beginning June 1, 2006, all diesel fuel produced and sold for vehicular use in California must meet a 15 ppm maximum sulfur limit, in addition to meeting all of the current low aromatics CARB diesel specifications. The definition of "vehicular use" in California includes on-highway vehicles and non-road vehicles (e.g. agriculture and construction equipment). Locomotive and marine vehicles are not included in the definition of vehicular use
Diesel FAQ
After many annoying years of hearing how ULSD (Ultra-Low-Sulfur Diesel) will finally make diesel vehicles clean enough to meet the minimum emission criteria (which isn't even remotely close to the SULEV rating), it turns out that goal could not be achieved.
Defeat before the competition had a chance to actually begin is a very unexpected victory.
I planned on having to deal with the nonsense of vague claims, misleading data, and the usual dismissal of smog-related emission importance. But instead, there won't be anything for years to come. And by the time there is, the next generation hybrid will be available... making efficiency a very difficult factor to compete with too.
Since hybrid owners get accused of being smug anyway, it's awfully tempting to take advantage of this newest fatal blow against diesel by gloating. So, perhaps I will.
JOHN
The only fatal blow will be to the over complex hybrids when the auto makers get past the ignorance displayed by both the EPA and CARB. It will be much sooner than you think. I say October 2006 for a flood of diesel vehicles coming from Europe. As usual the Japanese will have to copycat to catch up.
Mercedes-Benz is here in California at this very moment demonstrating its BLUTEC diesel full size GL SUV, which can be turned into a diesel-Hybrid. And General Motors Corp., and I believe BMW are moving ahead with the development of diesel-hybrid trucks, which are about 30 percent more fuel-efficient than the politically correct, over-hyped gasoline-electric
Washington Post
While consumers are purchasing Prius and Camry-Hybrid as quickly as they can be delivered, not a single diesel sale of Jetta, Golf, or Beetle will occur... because none will be available.
Whether or not there might be a cleaner Pickup or SUV available later is completely meaningless to those that want a car. VW will have nothing to sell to compete with those PZEV rated hybrids.
JOHN
However if your No 1 criteria is that the vehicle will not be a Corolla or Civic or smaller...or... if the prime criteria is that the vehicle must have a Navi system or keyless entry or Bluetooth or 6 disc changer then the Echo is not in the running.
If you can get all of this and better fuel economy than an Echo, then the Prius begins to look like an option.
If the primary result then is transferring money from Big Oil and the Mideast to Japan, I will definitly take that option.
The criteria for a car is that it gets one where they want to go. Thats luxury enough! Im afraid if we keep comsuming like we are we're going to price ourselves out of the personal transportation market. (No that wont work its too old fashioned(