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Wide varieties of vehicle Engine Management Systems are designed by different Tier#1 suppliers to meet highly complex requirements with the help of electronics. Emerging technologies and features of Engine Management Systems require a number of strategies for reducing the overall timing for verification with high quality testing. Analysis and decoding of data especially for highly critical and complex such as gasoline direct injection (GDi) engine fuel delivery output, high pressure fuel pump (HPFP), spark control output and different varieties of engine position signals are time consuming. This paper introduces Virtual Engine Control Module (VECM) technology to solve the problem of decoding complex signals and high level verification. A proposed test bench setup consists of VECM, ECM, simulator and real actuator load with complete software flashed inside the ECM.

As fuel prices continue to rise automotive manufacturers continue to push their suppliers to provide technology that improves the potential fuel efficiency of their applications. In addition there is an increasing trend towards smaller, lighter and more compact vehicles to mitigate the automotive carbon footprint. These movements necessitated the development of a new compact, low mass, variable displacement compressor to match the requirements for these smaller and more efficient vehicles. The new Delphi MVC, or Miniature Variable Compressor, meets these requirements by integrating the high efficiency of our latest swashplate variable compressor design into a compact and lightweight package. This design can be offered in a range of displacements from 80 to 100cc and can be offered as either internally or externally controlled to support the customer's needs.

The progressive trend towards the GDi engine downsizing, the focus on better fuel efficiency and performance, and the regulatory requirements with respect to the combustion emissions have brought the focus of attention on strategies for improvement of in-cylinder mixture preparation and identification and elimination of the sources of combustion emissions, in particular the in-cylinder particulate formation. This paper discusses the fuel system components, injector dynamics, spray characteristics and the single cylinder engine combustion investigation of a 40 [MPa] capable conventional GDi inwardly-opening multi-hole fuel injection system. It provides results of a study of the influence of fuel system pressure increase between 5 [MPa] to 40 [MPa], in conjunction with the injector static flow and spray pattern, on the combustion characteristics, specifically the particulate and gaseous emissions and the fuel economy.

In previous work, Gasoline Direct Injection Compression Ignition (GDCI) has demonstrated good potential for high fuel efficiency, low NOx, and low PM over the speed-load range using RON91 gasoline. In the current work, a four-cylinder, 1.8L engine was designed and built based on extensive simulations and single-cylinder engine tests. The engine features a pent roof combustion chamber, central-mounted injector, 15:1 compression ratio, and zero swirl and squish. A new piston was developed and matched with the injection system. The fuel injection, valvetrain, and boost systems were key technology enablers. Engine dynamometer tests were conducted at idle, part-load, and full-load operating conditions. For all operating conditions, the engine was operated with partially premixed compression ignition without mode switching or diffusion controlled combustion.

As automotive and commercial vehicle OEM's continue their quest to reduce cost, product selection, quality, and reliability must be maintained. On-engine and wheel located connection systems create the greatest challenges due to the extreme levels of vibration. In the past, devices were fewer, and there where less direct connects in high vibration locations (Engine/ wheel sensors, electronic controllers, fuel injectors). Instead, small wire harnesses (“pigtails”) were commonly used. These pigtails can dampen the effect of the environment which includes mild to severe vibration by keeping the environmental effect away from the electrical connection contact point. Electrically connecting directly to the device creates new challenges in the connection system with the increased threat of fretting corrosion. Suppliers supporting OEM's are attempting to meet these direct connect requirements with lubrication, precious metal plating, and high contact force contacts.

To meet future particulate number regulations, one path being investigated is higher fuel pressures for direct injection systems. At operating pressures of 30 MPa to 40 MPa, the fuel system components must be designed to withstand these pressures and additional power is required by the pump to pressurize the fuel to higher pressures than the nominal 15MPa to 20MPa in use today. This additional power to the pump can affect vehicle fuel economy, but may be partially offset by increases in combustion efficiency due to improved spray mixture preparation. This paper examines the impact on fuel economy from increased system fuel pressures from a combination of test results and simulations. A GDi pump and valvetrain model has been developed and correlated to existing pump torque measurements and subsequently used to predict the increase in torque and associated impact on fuel economy due to higher GDi system pressures.

Variable displacement compressors have proven to be more energy efficient than the equivalent compressor with fixed displacement for mobile A/C applications. Variable displacement compressors de-stroke rather than cycle to prevent the evaporator from freezing. Cycling an internally controlled variable compressor is counter intuitive, yet results in a 15-20% reduction in the energy used by the compressor as demonstrated by tests on multiple vehicle applications. Externally controlled variable compressors have the highest energy efficiency and extending cycling to these compressors during cool temperatures reduces the compressor energy consumption by 10%.

With more vehicles adopting fuel-saving engine start-stop routines and with the number of hybrid and electric vehicles on the rise, automotive A/C (air conditioning) systems are facing a challenge to maintain passenger comfort during the time when the compressor is inactive due to engine shut down. Using PCM (Phase Change Material) in the evaporator enables it to store cold when the compressor is active and release it to the cooling air stream when the compressor is not running. A unique feature of Delphi's design is that a refrigerant thermosiphon mechanism inside the evaporator drives the energy transport between the PCM and air stream. Delphi's PCM evaporator extends comfort for short duration idle stops, reduces emissions, and increases fuel economy and electric drive range. In this paper, the design aspects of a thermosiphon based PCM cold storage evaporator are described and the performance and operation of the PCM evaporator in a MAC (Mobile Air Conditioning) system discussed.

As the emissions and fuel economy standards for internal combustion engines become ever more stringent, a variety of valvetrain control methods have been developed to improve engine performance. One of these is camshaft (CAM) phasing, which controls the angular position of the CAM relative to the crankshaft allowing changes to the timing of valve lift events. This method has demonstrated advantages including broadening the engine torque curve, increasing peak power at higher RPM, reducing hydrocarbon and NOx emissions, and improving fuel economy. In addition, external EGR systems can be eliminated because internal cylinder dilution control can be achieved by varying CAM timing. Current implementations of CAM phasing use oil-pressure-based electro-mechanical systems. While these systems are relatively low cost and have proven to be robust, they have disadvantages at low oil temperatures and pressures (such as during cranking events).