Common Technologies, Uncommon Fuels, New Challenges
By Robert McIntyre
There is a "shade tree law" from the 1970s that states that computing capacity doubles every few years. In fact, computing capacity for the size of the computer or device has outstripped that by several orders of magnitude in the last five years. As evidence of that, we now see cell phones that were only found in science fiction or spy novel stories not so long ago and I-Pods and personal audio players that put 10,000 recordings in the palm of a 14-year-old's hand.
This technology explosion has profoundly impacted the engine and motive power industry from top to bottom; from lawnmowers to 500-ton GCW mine trucks. Just in time as well, since the EPA and its equivalents in most of the industrialized world have adopted ever more stringent emissions requirements that would be absolutely impossible to meet without computer controls of engine operation and performance.
The other aspect of this merger of mechanical and electronic technologies is the convergence of diesel and gasoline engine management technologies so that in the more advanced versions of each type of engine, just about the only things different are the compression ratios, rpms and the strength of the working parts.
Finally, the most important part of this revolution is the restriction of information that is starting to strangle the non-OEM world, which is likely to continue in the future. Simply put, if a computer is going to be used to control and monitor critical functions in a power unit, it is still a computer, and acts and works like a computer. This means no moving parts and virtually no opportunity to reverse engineer what is in the brain that measures and controls the engine.
To see how this works, the first thing that we have to understand is what differences, if any, there are between advanced 2005 gas and diesel engines. Consider the following:
Both gas and diesel engines inject fuel directly into the cylinders using electronically controlled common rail injection systems with one injector per cylinder. (Honda now has a gas engine that only uses a spark plug for starting, with "compression ignition" thereafter);
Both gas and diesel engines can be made without any throttles or upstream air flow controls;
All fuel quantity, quality and timing of injection are controlled by computer means with no mechanical intervention;
Any performance enhancements like supercharging, turbocharging or both are computer-controlled;
Valve timing and lift are electronically controlled;
Any emissions-related combustion enhancements like excess air, exhaust gas recirculation, lean burn or similar strategies are computer-controlled.
Much of this advancement is coming from Bosch in Germany, where the emissions standards are, in some cases, stricter than the USA. For example, the two illustrations shown on page 26 illustrate the gas fuel supply for a common rail system and one for a diesel as well. Both are pressurized by mechanical or electric pumps that are not "tied" to the engine for the purposes of injection timing or otherwise.
In addition, there are few diesels or gas engines in vehicles that are not "drive by wire" with the "gas pedal" attached to the computer and a throttle body or other air regulation system completely controlled by the computer responsible for engine speed regulation. This system can take several forms;
1) In a diesel, there is no air flow control, all speed and power controls are through the fuel injection, turbo boost pressure controls and variable cam timing, all controlled by the computer.
2) In many gas engines, a throttle plate positioned by an electric motor is used, but in some more advanced systems, there is no throttle plate and the amount of air admitted is completely controlled by the timing and lift of the intake valves; again, computer controlled (BMW's big 750 and 760Li and the new "3" series are examples of vehicles using this technology).
Those of us who can be dated by remembering cars operated with "spark, mixture and throttle" controls on the wheel or who fly private piston powered aircraft can appreciate the value of instantly and in some cases, anticipatory adjustment of these critical elements of engine operation.
Finally, this electronic revolution has now gone past the point where the computer can vary intake and exhaust valve timing and lift by electro-hydraulic control of the cam or cams using engine oil for a true camless engine. Yes, the cam itself is a dead duck in the foreseeable future as International/Navistar has built and run a camless diesel for hundreds of thousands of miles with unprecedented success (see illustration).
In simple terms, we have the heavy duty truck owners and hot rodder's dream engine all in one black box. We now have the ability to infinitely change the valve opening and closing time, the lift of the valve, the moment that fuel is put right in the cylinder and in what form. There are no more "hot" cams with no low end, no more 15 -18 speed gearboxes to bootstrap diesels with 600 rpm power bands, no detonation or diesel knock at idle, and incredible fuel economy and emissions that were only bureaucrat's dreams five years ago.
Imagine an engine that can open and close its valves different amounts at different degrees of crank rotation at any speed, and can control not only the amount of fuel injected but the exact point in the crank's journey where it will be sprayed directly into the cylinder in a precise pattern. This is a far cry from hoping that the right mixture will wander down the intake manifold at the right time, hopefully to be ignited by a weak spark timed by mechanical and vacuum "advances," or that the clock works in the mechanical fuel injection and will have the right answer for the load and speed requirements at that moment when the truck hits the bottom of the big hill.
This concept goes even further, so that multiple injections of different amounts of fuel at different times can be achieved. This means that at idle the timing can be retarded and a light injection can take place in one or more instances, keeping the cylinder and piston warm and ready to work, the catalytic converter hot and the idle smooth (and quiet, in a diesel).
When load is applied the whole game can change in an instant and the timing, injection and amount of air and/or boost can be anticipated and delivered as needed. Similarly, while running at higher rpms at light load, the least amount of fuel necessary to keep the load satisfied can be used; again, sent in to work at exactly the right time or times to maximize efficiency and minimize emissions. This also works great with cylinder disabling such as that found on the new Chrysler Hemi and some Mercedes and BMW engines.
Injection quantity and quality are the key in emissions strategies; multiple injections of different quantities of fuel at different points in the crank rotation govern the burning of the fuel and the power and pollutant outputs. For example, a little whiff to start the fire and warm up the piston crown, a bigger dose to get the fire burning really hot, a big squirt just before the pressures peak in the combustion chamber and a final whiff to catch any air that was not already burned as the piston races to BDC. These strategies are not different for gas and diesel; just the details are ironed out for each engine and application.
This can mean 95% of available torque just off idle, no pumping losses at light load and high rpm, any kind of power curve you want for your application, and the ability to make one basic engine architecture serve many different vehicles and needs. This has been the rule in diesel for some time, one displacement and "package envelope" can be rated to develop 250 or 550 horsepower with any power and torque curve you want. This commonality will go a long way to making the wizardry cost less as it makes up for the cost of several engine sizes for different uses.
In essence, from the times of steam where the "engineer" could control the steam pressure, steam temperature, valve timing and valve lift; through the "spark, mixture and throttle" controls of the '20s and the hundreds of different carburetors, ignition systems and fuel injection pumps with all sorts of mechanical or hybrid add-on controls, the events in an engine were always a compromise born of the need for power and control. "Nothing is perfect" could best describe this system of thought, so the best compromise for the most likely to be encountered conditions was the rule.
That was the past. Today, not only does the computer figure out what the load and speed needs are and the emissions restrictions, but it "learns" the operating conditions and driving habits of the user and makes new plans as it operates. In addition the computer talks and listens to the computers that run the transmission - or in the case of heavy equipment, the hydraulics as well - so that every question is not only answered, but anticipated as well.
The computers learn how to match the "spark, mixture and throttle" for every condition, just like when Grandpa advanced the spark and richened the mixture at the bottom of "Three Mile Hill" so that his Model T had plenty of power to make the top without knocking or overheating. Now as the technology advances even further, even engine wear, rolling resistance and other load shapes will be accounted for in the question and answer sessions constantly taking place between the computers and the sensors.
Unfortunately, the downside to this great new age IS the computer. When the old shop boss asked the whiz kid where the grease fittings and adjustment screws were on the new process computers, he was only partly joking. It is very difficult to diagnose and fix something you can't see or measure. My mechanical engineer grandfather - who successfully made the jump from steam to diesel on the railroad - used to say, "with a steam locomotive it took ten minutes to find the problem and ten men and ten hours to fix it - on a diesel electric, the opposite was the case." You can't fix it when you can't find what is broken.
Where this leaves all of us in the aftermarket is that without the key to the computer vault where the information that makes everything work lives, we cannot fix, rebuild or test our work after installation or on the dyno stand. This is great for the OEMs: by keeping the codes secret they can control the repair industry and they have the government as their partner and personal policeman.
In the last big battle between the OEMs in the engine business and the EPA, the deal was that the emissions limit timetables were kept at a compromise, but the government bought the OEM line that "only the OEMs should be trusted with the computer codes to protect the environment" from the rest of the industry and the users.
Unfortunately, a very high percentage of Congressional staffers and EPA employees are lawyers or others with no technical background and they bought this BS and wrote it into the regulations…a perfect example of the Golden Rule: those with the gold (OEMs) make the rules.
It gets worse. In many instances, the OEMs are going to court and winning consent settlements that state that the codes and repair information are "trade secrets" or "proprietary" and thus, if put into the light of day for everyone's use, the OEMs would be out of business and the black skies would resemble nuclear winter from the uncontrolled emissions of improperly repaired/rebuilt engines due to improper use of the computer codes.
In this country however, the laws are made and enforced by lawyers and others who can't/don't/aren't interested in understanding the technology; and thus take the safe route and believe the OEM line(s): better to put the bat to some repair shop or rebuilder than risk the "end of life as we know it" due to exhaust pollution.
See Mike Conlon's sidebar article "California HD Rule Likely to be Model for EPA" for more about the challenges involved in getting access to heavy duty repair and diagnostic information.
Imagine that it is three years from now and you are looking at the top of an engine with the "valve cover" off. All you can see are two rows of solenoids and hydraulic actuators, some pipes and injectors, and a lot of wires. A computer is clamped to the engine or on the firewall with a diagnostic plug. The spark plugs have individual coils and a simple harness, or if it's a diesel, maybe some turbo controls as well. It does not run right and you have no way to even diagnose the problems - there are no grease fittings on the computer.
The aftermarket has unprecedented challenges today. In the past it was tough enough to just keep up with new technology and master it to keep customers happy; today not only is the technology virtually merging between main engine types, but it is being kept away from the industry by the government and the OEMs. In summary, not only do we have to learn, but we have to fight for the right to learn as well.
About the Authors:
California HD Rule Likely to be Model for EPA
by Mike Conlon
With the increasing complexity of today's engine systems and the all-encompassing reach of the vehicle computer, the technician who is trying to rebuild or service an engine is faced with three daunting tasks. First, he must have the proper equipment to diagnose any problem. Second, he must have access to all the information necessary to repair the problem. And finally, if the problem requires a "fix" to the computer software, he must have the ability to make that fix.
Until now the independent technician was generally at the mercy of the heavy-duty engine manufacturer and often found himself at a disadvantage to his dealership counterpart. Generic diagnostic tools are available but often they cannot identify many of the faults recognized by the manufacturer's more enhanced tools. Information on a particular problem may or may not be available, but even if it is, it can be hard to find. And many times the only way to complete a repair if a software change was necessary was to have the engine or vehicle taken to the nearest dealership where the proper reprogramming equipment was available. Hopefully, all of that is about to change.
In the early '90s Congress amended the Clean Air Act to require on-board diagnostic (OBD) systems to monitor the emissions from automobiles. At the same time it also recognized that use of such systems could be abused by manufacturers to limit those who could repair parts covered by the OBD system by restricting access to the OBD computer and related information. To prevent such efforts and the negative impact on independent service technicians and rebuilders, Congress required that the manufacturers provide access to the OBD computer and the service information necessary to repair emissions related parts to anyone who needed it.
As a result EPA passed regulations that require that all enhanced diagnostic tools available to a manufacturer's dealers must be made available to independent technicians at a fair and reasonable price. Additionally, the data stream and bi-directional control information incorporated into those tools must be made available to generic tool manufacturers for use in their tools. Manufacturers must also make available general descriptions of the OBD system and its functioning. All information, necessary to facilitate the repair, including service and repair procedures, TSBs, wiring diagrams, troubleshooting guides and training materials must also be available. And this information must be made available on a Web site which meets certain criteria for ease of access and use. Finally, the manufacturers also had to make available to independents, at a fair and reasonable price, the tools they made available to their dealers to reprogram the engine computer to correct errors and the reprogramming information in those tools to generic tool manufacturers so that they could incorporate it into their tools. California adopted similar requirements.
While the above regulation benefited those independent technicians working on automobiles, it did nothing for the heavy-duty aftermarket because OBD systems and the rules regarding access to them only applied to vehicles under 14,000 lbs. GVW. However, both EPA and California have recently taken steps to require OBD systems on heavy-duty vehicles and to allow similar access to information and tools for independent heavy-duty technicians.
California has taken the lead in requiring OBD systems for heavy-duty vehicles. It now requires limited OBD systems on heavy-duty vehicles starting with model year 2007, and it will consider a new regulation this month, which will require much more extensive systems to be phased in to a manufacturers engine families between 2010 and 2013.
At the same time it has already passed a regulation requiring the heavy-duty engine manufacturers to create Web sites with the same diagnostic and repair information that must be provided to automobile technicians. This Web site must be available in 2007 for vehicles of that and all later model years.
Causing more of a problem is California's effort to require these engine manufacturers to make available enhanced diagnostic and reprogramming tools to technicians and the information contained in those tools to the generic tool manufacturers. The engine manufacturers have balked at providing such tools and information. They claim that because of the flexibility that they need to build into their computers to allow their engines to work with many different equipment configurations that many of the functions contained in their diagnostic and reprogramming tools, if made available to the aftermarket, would create performance or safety problems in vehicles and are not necessary for independent technicians to service or repair the vehicles. For those reasons they have argued vehemently that only some of the functions of these tools be made available to independents. The aftermarket and the generic tool manufacturers have viewed such claims with much skepticism and have concerns that they may be a ruse to avoid having to furnish essential information. As an example, it seems hard to believe that any function in a diagnostic tool would cause a problem because that tool is normally not designed to make changes to the computer but merely to extract information from it. However, the engine manufacturers have said that certain functions of their diagnostic tools do create certain temporary changes in the software which could cause problems. Discussions among California, the engine manufacturers and the tool manufacturers have been unable to resolve the issue. Originally, the rule requiring that the tools and their operating information was to have been finalized this summer. However, due to the obstinacy of the engine manufacturers, consideration of it has been postponed until later this year or early next year. Moreover, even when passed the rule will not apply to engines and vehicles prior to the 2010 model year.
California has now asked the engine manufacturers to give it a list of those functions which it believes could cause problems if made available to the independent aftermarket and which are not necessary for servicing the engine together with an explanation of why access to each particular function will cause a problem. Once this information is received California intends to review it and discuss it with the generic tool manufacturers and the aftermarket to see if any agreement can be reached. Therefore, over the next few months there should be much lobbying by affected interests to convince California that either access should or should not be limited and if limited, to what extent.
EPA has lagged in adopting both rules requiring OBD systems for heavy-duty vehicles and information access to such systems. It has indicated that it wants to coordinate its rule with the California rule to the greatest extent possible to make compliance easier for the manufacturers. In fact it now appears likely that EPA will be content to merely wait until the California rule is final and then pattern its rule after it. Therefore, the effect of whatever happens in California will have significant repercussions throughout the country.
Robert McIntyre is the fouding partner of the Cleveland firm of McIntyre, Kahn & Kruse, Co., LPA. He has extensive experience in Commercial, Intellectual Property, Banking, Corporate and Commercial Transactions and Environmental Litigation.
Mike Conlon is legal counsel for the Engine Rebuilders Association (AERA) and the Automotive Parts Rebuilders Association (APRA). He is an attorney with the Washington, DC, firm of Conlon, Frantz, Phelan, Knapp & Piers.