Clean Diesel? Isn't that an oxymoron? If you've ever sat next to a diesel-powered pickup truck at a stop light and had diesel fumes and soot blown in your face from a four inch exhaust pipe, you know what I'm talking about. Traditional diesel engines are about as eco-friendly as a smoke belching coal-fired steam engine from yesteryear.
But diesel technology has advanced considerably in recent years. The latest renditions on Otto's compression ignition engine bear little similarity to the black soot belchers of a decade ago. Common rail high pressure direct injection systems with sophisticated electronic controls have finally tamed the diesel, and made it perfectly acceptable as an alternative to gasoline-powered engines for passenger cars as well as light and medium-duty trucks.
Currently, diesel power-powered cars and light trucks account for less than four percent of the North American vehicle population. The German auto makers are the only ones selling diesel-powered cars in the U.S. Yet in Europe, diesel-powered cars account for nearly 60 percent of the vehicle population.
Why, you ask? Because diesels are up to 30 percent or more fuel efficient than a comparable gasoline engine of the same displacement and horsepower rating. Diesel engines get better mileage because they burn their fuel more efficiently. A diesel engine has a much higher static compression ratio than a gasoline engine, so it achieves more thermal efficiency from the fuel it burns. In other words, it produces less waste heat that goes into the cooling system and out the tailpipe compared to a gasoline-powered engine.
So if we all want better fuel economy, why aren't all the auto makers offering diesel-powered cars? Emission regulations have hampered the sale of diesel-powered cars in the U.S. But now that we have ultra low sulfur diesel fuel available, and new electronic diesel injection technology and after treatment systems, diesels can meet the toughest tailpipe emission standards.
Since 1988, Clean Diesel technology has reduced oxides of nitrogen (NOx) emissions 99 percent, and reduced particulate matter (soot) in the exhaust 98 percent! These are HUGE gains as well as proof of how clean today's diesel engines can actually run.
Green Car of the Year Tour
I recently attended a Clean Diesel event at the Argonne National Laboratory near Chicago, IL. The event was part of the 2010 Green Car of the Year Tour sponsored by the Green Car Journal magazine. The tour included several diesel-powered Volkswagen Jettas TDI models, and the Green Car of the Year winner, the 2010 Audi A3. The Audi A3 gets 42 mpg on the highway with a 2.0L turbodiesel engine, which is 50 percent better than the exact same car with a gasoline engine. All of the vehicles were available for journalists to test drive. My impression? All of the diesel-powered cars started right up, idled smoothly and quietly, and ran great. . . The 2010 clean diesel powered Audi A3 won the Green Car of the Year Award.
If you've never driven one of these state-of-the-art Clean Diesel German cars, I would suggest you do so. You can't tell them from their gasoline -powered counterparts. There's no traditional diesel rattle, no clatter when you step down on the accelerator, no black soot in the exhaust. Just clean, smooth power with lots of low end torque.
A couple of years ago, I also attended an event sponsored by Bosch in Detroit that was promoting their Clean Diesel injection technology. They had a number of European Mercedes and BMW models, some of which were gasoline-powered and some of which were diesel-powered. The badges had been removed from the cars so the journalists couldn't tell which type of engine was powering the vehicle they were driving. I couldn't distinguish any noticeable difference in noise, smell or performance between the diesel-powered cars and the gasoline-powered cars -- which was exactly the point of the demonstration.
Now that Clean Diesel technology is truly available, we will probably see more and more of these vehicles on the road in the years ahead. Proponents of Clean Diesel technology say it can be just as fuel efficient and much more cost effective than hybrid technology.
Argonne Testing Advanced Vehicle Technologies
Argonne is the U.S Dept of Energy's lead laboratory for researching and testing advanced vehicle technologies, including Clean Diesel engines, alternative fuels, hybrid and electric vehicles. The scientists at Argonne are studying and evaluating lots of new technologies to find out how they work, which ones work the best, and what type of fuels offer the best results.This is Argonne's Modular Automotive Technology Testbed (MATT). It is a rolling chassis with interchangeable modules that allow Argonne scientists to test various combinations of powerplants (gasoline or diesel) with hybrid electric drivetrain components on a four wheel chassis dyno.
The German Clean Diesel engines are designed to run on ultra low sulfur diesel fuel, but can also run on B5 (a five percent blend of biodiesel with diesel fuel). Research is being done to determine the suitability of higher biodiesel blends, different types of biofuels, and also diesel-ethanol blends, and diesel-butanol blends (butanol is a different type of alcohol that can also be made from corn, and has less affinity for water, making it better suited for transport through pipelines than ethanol). For more information about butanol, Click Here.
Argonne's scientists are also investigating the possibility of running diesel engines on low octane gasoline as well as other alternative fuels such as natural gas and hydrogen. Agronne's advanced combustion research is looking into the processes that occur inside a diesel combustion chamber when the fuel is injected, mixes with air and ignites. Argonne was the first to document the presence of shock waves that occur during the injection event, which is helping scientists figure out how to optimize combustion efficiency while minimizing the formation of particulate particles (soot).
One of the more advanced fuel projects Argonne is working on is the development of diesel nanofluids. Tiny nanoparticles of metals, oxides, carbides, nitrides or nanotubes are added to diesel fuel to change the way the fuel burns so it will release more heat and energy to improve fuel economy.
Argonne also played a key role in evaluating a number of vehicles that were competing for the Automotive X-prize, the goal of which is to achieve 100 miles per gallon with a production-capable three or four-wheeled car. Is that cool or what?
Friday, October 1, 2010
Friday, April 20, 2007
Where to get your car repaired -- and not get scammed
WHERE TO GET YOUR CAR FIXED
One of the most common questions I hear is, "Where should I take my car to get it fixed?" My answer is to take it to a repair facility that (1) has a good reputation (ask friends and neighbors where they take their vehicles), that (2) is affiliated with a group such as AAA and/or has ASE certified technicians, and (3) appears to be clean, friendly and competently managed. The shop should also adhere to the Code of Ethics and repair standards put forth by the Motorist Assurance Program (MAP).
Most repair facilities are honest and are NOT trying to take advantage of you. Sure, there are some bad apples in the the repair business, but there are crooks in every kind of business from home repair scam artists to top business executives. From what I have seen, most auto repair problems are due to misunderstandings or miscommunication between the motorist and repair facility (they thought you wanted one thing and you got something else, or they misunderstood your problem), or they misdiagnosed your vehicle and the technician replaced the wrong part(s). In other words, they did not try to rip you off or cheat you. They misunderstood you or did not perform the correct repair.
As long as your vehicle is under warranty, you can return to your new car dealer for free repairs (for parts that are covered under warranty). Almost all new cars and trucks today have a 3 year/36,000 mile bumper-to-bumper warranty that covers ANYTHING that goes wrong. All new vehicles also have a federally mandated emissions warranty that covers the engine computer and catalytic converter for 8 years/80,000 miles (longer in California). The vehicle manufacturers may also offer an extended powertrain warranty that covers major repairs to the engine, transmission and drive axles. Items that may NOT be covered under warranty include common wear items such as filters, brake pads and tires.
Once your vehicle is out of warranty, you can take it anywhere you please for repairs. In fact, you are NOT required to return to the dealer for maintenance or repairs while the vehicle is under warranty (you can take it to ANY repair facility). But the vehicle manufacturer will usually NOT pay for any repairs performed by any unauthorized repair facility -- except in rare emergencies where a vehicle has broken down too far away to be towed to the nearest dealer.
As a rule, independent repair shops are generally less expensive than new car dealers. Franchised repair facilities such as muffler shops (Midas, CarX, Merlin, etc.), tire dealers (Goodyear, Firestone & independents) and retailers (PepBoys, Sears, etc.) are also very competitive with their pricing.
As for repair competency, it can vary a great deal from one repair facility to another. New car dealers have access to the latest factory authorized training and tools, and specialize in the brand(s) of vehicles they sell. But big dealerships are also less personal. You rarely deal directly with a technician. Instead, a service writer talks to you, hears your problem and writes up a repair order. Miscommunication sometimes happens and you do not get the right repairs or service. The service writer is also a salesman who will probably try to talk you into buying additional services you may not need (your 50,000 miles scheduled maintenance, for example, which is nothing more than an oil change, some new filters and a quick inspection of a laundry list of things that should always be checked every time your vehicle is serviced or repaired).
Independent repair shops and specialty repair shops (those who only work on imports or specialize in alignments, brakes, transmissions, air conditioning, electrical, etc.) tend to be small family-owned and run businesses. You are usually on a more personal level with these people, and may even talk face-to-face with the technician who works on your car. Many independent shops are highly skilled and work on ALL makes and models. This requires a much broader range of expertise than a dealership -- and more diagnostic equipment and tools. Some shops, though, are behind on the learning curve and may not be up to speed on the latest technology. Or, they may not have an up-to-date scan tool or other special tools that may be required to service your vehicle. Even so, such a shop may be fine for basic maintenance and repairs.
The kind of repair facility to avoid is one that is NOT concerned about their reputation or repeat customers, and are only out to scam as many people as fast as they can. These shops are not in the repair business for the long haul. They are only in it to make a fast buck. They probably have not been in business very long. They are typically located in "high traffic" areas where they can snag a lot of drive-by customers. They may be located near an expressway where out-of-towners are apt to break down. They usually have high employee turnover and typically hire beginners or less experienced technicians. They often use "scare tactics" to sell parts and services, or try to pressure you into agreeing to major repairs. They are NOT affiliated with any reputable service organizations such as AAA, ASE, their local chamber of commerce or local repair shop organizations. They do not invest any money in training their employees or buying new equipment. The facility itself may or may not be clean and neat (you cannot judge competency and honesty by appearances alone). And they offer no guarantee or a very limited warranty on the work they perform. Avoid these kind of places at all costs!
General Advice for finding an honest and competent repair facility:
Patronize a repair facility that has been recommended to you by friends or family.
If you are satisfied with a repair facility, give them your repeat business. Build a lasting relationship.
Do NOT pick a repair facility at random or based only on advertisements or price specials.
The repair facility should follow the Motorist Assurance Program (MAP) Standards of Service. You can obtain copies of these guidelines from the MAP website at www.motorist.org Give the shop a copy if they do not have one.
Always ask for a written repair estimate BEFORE work begins. (This is required by law in many states.)
The final repair bill should NOT exceed the estimate by more than 10 to 20%. (this is also dictated by law in many states, though circumstances may justify a higher final bill.)
Make sure the estimate lists all parts and labor charges. (and ask for an explanation of any items you do not understand or have a question about.)
If you have any doubts about the work performed, ask for your old parts to be returned. (you may need them as evidence if you have been scammed.)
If you have a dispute with a repair facility, take your problem up the chain of command, then contact your Better Business Bureau if you cannot get the matter resolved. Take legal action as a last resort.
Pay your repair bill with a credit card (if allowed) (You can always dispute the charges later when your credit card bill arrives.)
Larry Carley is a well-known automotive technical writer with 27 years of automotive writing experience. He writes for professional automotive trade magazines, and has his own automotive website at http://www.aa1car.com
Tuesday, October 17, 2006
Which is Best: Diesel or Electric/Gas Hybrid?
Diesel Engine or a Gas/Electric Hybrid? 
The short answer to diesel versus hybrid is the choice depends on what you want to use the vehicle for. If you want a truck with lots of towing power, buy a diesel. If you want a fuel efficient commuter car for urban driving, buy a hybrid car like the Toyota Prius, or buy a turbo diesel-powered car like a VW.
Unfortunately, your purchase options are very limited because hybrid gas/electric powertrains and diesel engines are only available in a few cars. Diesels have long been a popular option in light trucks and the availability has been pretty good. But diesel cars have been in short supply – and will get even harder to find for the next year or so thanks to new emission regulations.
As usual we get the wrong regulations at the wrong time. The EPA decided it would be a good idea to require cars and light trucks with diesel engines to meet the same emission regulations as cars with gasoline engines. The Tier 2 emission regulations, which all cars must comply with start in 2007, require a fleet average of 0.05 grams per mile of oxides of nitrogen, a figure today’s diesels cannot meet without low sulfur fuel and electronic direct injection technology. The rules also limit particulate (soot) emissions, which requires diesels to have some type of particulate filter in the exhaust. To make matters worse, California, New York, Massachusetts, Vermont and Maine have all adopted even tougher diesel emission standards than the federal EPA standards.
In Europe, where gasoline costs several times as mucha s it does here, and where diesel emission regulations are less strict, diesel powered cars account for over HALF the car population. The European limits for oxides of nitrogen are EIGHT times higher.
Unless the new regulations are relaxes or repealed (fat chance for that happening), the diesel option in cars and some light trucks (depends on size & weight) will go away in 2007, and will only slowly return as the technology improves.
Diesel Options:Currently, the only diesel-powered cars available are:
Mercedes E Class E320 CDI
Jeep Liberty CRD
VW Passat TDI
VW Touareg TDI
VW Turbo Diesel Golf TDI
The main attraction of a diesel engine is that it is more fuel efficient than a gasoline engine: up to 30% better fuel economy as a rule than a comparable gasoline engine of the same displacement.
A diesel engine uses high compression rather than spark ignition to burn the fuel. This eliminates the need for an ignition system (no spark plugs, coils or ignition module), but it does require a very high pressure fuel injection system, much higher than that on a gasoline engine. Most diesel engines have a glow plug system for cold starting. There is also no throttle on a diesel engine, so it sucks air more efficiently at idle and low rpm (reduced pumping losses). The trade off is that a lack of intake vacuum in the engine requires a separate vacuum pump for any vacuum operated accessories.
On diesel engines, fuel is injected directly into the combustion chamber as the piston approaches top dead center. The timing of the fuel injector is critical for good engine performance. Compression ratios are very high 18:1 or higher, so it takes a LOT of pressure (300 bar to 1800 bar) to inject the fuel into the cylinder or a precombustion chamber in the cylinder head. The heat of compression causes the fuel to ignite spontaneously. That’s why no spark plugs are needed.
Mechanically, a diesel engine is essentially the same as a gasoline engine except for the higher compression ratio. Diesels typically have stronger crankshafts, connecting rods and pistons than gasoline engines, and they typically run at lower rpms. Most of these engines are VERY durable and will last well beyond 150,000 miles with proper maintenance. Regular oil changes, however, are essential to maintain a diesel engine because they experience more blowby of combustion byproducts into the crankcase than gasoline engines.
Things that can go wrong with a diesel engine include injection pump problems, fuel injector problems, blown head gaskets, hard starting in cold weather if the glow plug system fails, and fuel waxing. Diesel fuel is actually a very light oil, so if it does not contain the right additives it can gel and plug up the fuel line or filter in cold weather.
Older diesels were also notorious for their idle clatter and black smoky exhaust. Many light truck diesel engines still have those attributes, but most of the direct injection passenger car diesel engines built by Volkswagen are relatively clean and quiet.
Would I buy a diesel powered car or truck? It would depend on the current price of diesel fuel versus gasoline, the cost difference to get the diesel option, and how much better fuel mileage the diesel gets over its gasoline counterpart. It would also depend on what I would be using the vehicle for (towing or general driving). Diesels do require a little more maintenance, and most owners who want to avoid cold weather starting problems are religious about using fuel additives in cold weather. I don’t see either of those things being a drawback if I wanted a diesel.
Hybrid Gas/ElectricHybrid electric vehicles use a conventional gasoline engine for propulsion, and an electric motor for supplemental power. The gasoline engine turns an alternator that keeps a large high voltage battery charged. Some hybrids are designed to shut off the gas engine when the vehicle stops moving to conserve fuel. The electric motor is then used to accelerate the vehicle up to a certain speed at which point the gasoline engine restarts and takes over. For maximum acceleration, the electric motor and gas motor may both provide power to the wheels. How the vehicle is programmed to balance gas power and electric power affects overall fuel economy as do driving conditions. That’s why a vehicle like the Toyota Prius gets better mileage in stop-and-go city driving than it does on the highway.
On other hybrids, the electric motor is used more like a supplemental power source to boost acceleration when extra power is needed. This allows the use of a smaller, more fuel efficient gasoline engine that gets better fuel economy without sacrificing too much performance.
The third approach is to have a start/stop only system, where the engine shuts off when the vehicle is stopped, and automatically restarts when the driver steps on the gas pedal. There is no electric propulsion.
Hybrid Vehicles Currently Available:Toyota Prius
Toyota Camry hybrid
Honda Accord hybrid
Honda Civic hybrid
Honda Insight
Lexus RX400H
Ford Escape hybrid
2007 Saturn Vue hybrid
2007 Mercury Mariner hybrid
A vehicle like the Toyota Prius is a technical marvel in my opinion. But it is also a VERY complex vehicle that is much more complex than any gasoline or diesel-powered vehicle. Consequently, the more complicated the system, the more stuff there is to go wrong.
As long as everything is working fine, I see no reason not to own a Toyota Prius or any other hybrid. But when these vehicles get some miles and age on them, I wonder how well they will hold up. Personally, I would NOT want to be the second or third owner of a used hybrid gas/electric vehicle. Why? Because of the high cost to replace the hybrid high voltage battery, because of the high cost to fix any electrical quirks or failures that may occur in the powertrain, and because replacement parts are NOT yet available in the aftermarket for these vehicles. New car dealers currently have a monopoly on these cars, and charge accordingly for parts and service. Most independent repair shops and garages are not yet up to speed on hybrid technology, so the new car dealer is about the only place you can take your hybrid if the electronic components or battery need repair. Ordinary stuff like brakes, tires, mufflers, cooling system, or the gasoline engine can be serviced anywhere.
The next-generation hybrids that will have a plug-in option and larger battery so the vehicle can operate more on electric power and less on gasoline power will make hybrids even better.
Diesels are BetterIn the meantime, I see clean direct injection diesels as the better short-term technology. The EPA needs to cut us some slack and roll back the new Tier 2 emission requirements for diesel engines. The environmentally-sensitive Europeans do not seem to be overly concerned about current diesel emissions, and are way ahead of us in diesel technology.
Diesel Sets New Land Speed Record 
On August 22, 2006, the JCB DIESELMAX set a new land speed record for diesel-powered vehicles with a speed of 328.767 mph at the Bonneville Salt Flats, Utah. Powered by two state-of-the-art JCB444-LSR engines developed by Ricardo, the JCB DIESELMAX beat the existing record by almost 100 mph. The race car was powered by two JCB444-LSR engines with two-stage inter-cooled turbo-charging, high pressure fuel injection and a low compression ratio, low temperature combustion system. All of these technologies are being developed by Ricardo for application on the high performance, ultra-low Tier II emissions diesel vehicles of the future.
Long term, the best powertrain choice in my opinion is a pure electric vehicle. Electric vehicles are environmentally clean, quiet and energy efficient. Fuel costs are potentially equivalent to over 100 mpg at today’s energy prices. If charged by electricity from cheap wind, hydroelectric or nuclear power sources, the economics make even more sense.
The battery technology isn’t quite there yet for a do-everything electric car, but ni-cad and lithium ion batteries are more than adequate for urban commuting, which satisfies the needs of about 90% of the population today. The problem is getting the major auto makers to commit to electric cars.
It’s no secret that car makers do NOT want to build electric cars. Why? Because electric cars are not profitable (at least not yet). Development costs are high, battery technology is still iffy, and the domestic car companies are heavily invested in internal combustion engine technology and production tooling. They would much rather sell us accessory laden SUVs and luxury cars than small fuel efficient vehicles regardless of what kind of power system is under the hood.
The domestic car companies cite all kinds of statistics that claim nobody wants electric cars, nobody would drive them if they were available other than wealthy left wing liberal Hollywood celebrities, and they would be too expensive for the average schmuck. Proponents of electric cars say the cars make perfect sense, that people would be standing in line to buy them if they were readily available, and that electric cars could be both affordable and practical if mass produced by major auto makers. I agree.
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