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A consortium of CONCAWE, EUCAR and the EU Commission's JRC carried out a Well-to-Wheels analysis of a wide range of automotive fuels and powertrains. The study gives an assessment of the energy consumption and greenhouse gas emissions for each pathway. It also considers macroeconomic costs and the market potential of alternative fuels.

This paper presents the findings of some fundamental characterisation of the deposits that form on the injectors of an air-assisted DISI automotive engine, including the effect of these deposits on engine performance when operated in different combustion modes, with varying fuel composition and additive content. A root cause analysis was undertaken, including an assessment of injector temperature and deposit chemistry. Fuels from a matrix designed around the European year 2000 gasoline specifications for T90, olefin and aromatic levels were used to study the effect of fuel composition on deposit formation. Two commercial gasoline detergent additives, of different chemistries, were used to investigate the impact on deposit formation. The results of the fuels study and deposit analysis are consistent with published theories concerning fuel composition impact on combustion chamber deposit (CCD).

Adding oxygenates to diesel fuel has shown the potential for reducing particulate (PM) emissions in the exhaust. The objective of this study was to select the most promising oxygenate compounds as blending components in diesel fuel for advanced engine testing. A fuel matrix was designed to consider the effect of molecular structure and boiling point on the ability of oxygenates to reduce engine-out exhaust emissions from a modern diesel engine. Nine test fuels including a low-sulfur (∼1 ppm), low-aromatic hydrocracked base fuel and 8 oxygenate-base fuel blends were utilized. All oxygenated fuels were formulated to contain 7% wt. of oxygen. A DaimlerChrysler OM611 CIDI engine for light-duty vehicles was controlled with a SwRI Rapid Prototyping Electronic Control System. The base fuel was evaluated in four speed-load modes and oxygenated blends only in one mode. Each operating mode and fuel combination was run in triplicate.

The influence of gasoline quality on exhaust emissions has been evaluated using four modern European gasoline cars with advanced features designed to improve fuel economy and CO2 emissions, including stoichiometric direct injection, lean direct injection and MPI with variable valve actuation. Fuel effects studied included sulphur content, evaluated over a range from 4 to 148 mg/kg, and other gasoline properties, including aromatics content, olefins content, volatility and final boiling point (FBP). All four cars achieved very low emissions levels, with some clear differences between the vehicle technologies. Even at these low emissions levels, all four cars showed very little short-term sensitivity to gasoline sulphur content. The measured effects of the other gasoline properties were small and often conflicting, with differing directional responses for different vehicles and emissions.

The transport of fuel-borne additives into the engine oil is a critical factor for the efficacy with which the additive functionality can be imparted on the engine. This paper describes the combination of Laser Induced Fluorescence (LIF) and Liquid Chromatography (LC) to determine the real-time additive concentrations and transfer ratios in a spark-ignition, 2-liter GM LHU engine. The current research used a continuous sample circuit from the engine sump which passed through an integrating cavity flow cell to enhance the LIF signal. In the absence of a fluorescence signature of any of the native additive species, a suitable fluorescing dye was selected to simulate the additive. After establishing rigorous calibration curves, LC was employed as a referee method to do a direct comparison with the LIF determined dye concentrations.

The objective of this study was to quantify the effect of pilot fuel injection on engine-out emissions of potentially toxic compounds from a modern diesel engine operated with different fuels including 15% v/v dimethoxy methane in a low-sulfur diesel fuel. Five diesel fuels were examined: a low-sulfur (∼1 ppm), low aromatic, hydrocracked fuel, the same low-sulfur fuel containing 15% v/v dimethoxy methane, a Fischer-Tropsch fuel, a California reformulated fuel, and a EPA number 2 certification fuel. A DaimlerChrysler OM611 CIDI engine was controlled with a SwRI Rapid Prototyping Electronic Control system. The pilot fuel injection was either turned off or turned on with engine control by either Location of Peak Pressure (LPP) of combustion or the original equipment manufacturer (OEM) calibration strategy. These three control strategies were compared over 2 speed-load modes run in triplicate. Thirty-three potentially toxic compounds were measured.

The objective of this study was to quantify engine-out emissions of potentially toxic compounds from a modern diesel engine operated with different fuels including 15% v/v dimethoxy methane in a low sulfur diesel fuel. Five diesel fuels were examined: a low-sulfur, low-aromatic hydrocracked (∼1 ppm) fuel, the same low sulfur fuel containing 15% v/v dimethoxy methane, a Fischer-Tropsch fuel, a CARB fuel, and an EPA number 2 certification fuel. A DaimlerChrysler OM611 CIDI engine was controlled with a SwRI Rapid Prototyping Electronic Control system. The engine was operated over 4 speed-load modes. Each operating mode and fuel combination was run in triplicate. Thirty three potentially toxic compounds were measured for each fuel and mode.

This oil category was driven by two new cooled exhaust gas recirculation (EGR) engine tests operating with 15% EGR, with used oil soot levels at the end of the test ranging from 6 to 9%. These tests are the Mack T-10 and Cummins M11 EGR, which address ring, cylinder liner, bearing, and valve train wear; filter plugging, and sludge. In addition to these two new EGR tests, there is a Caterpillar single-cylinder test without EGR which measures piston deposits and oil consumption control using an articulated piston. This test is called the Caterpillar 1R and is included in the existing Global DHD-1 specification. In total, the API CI-4 category includes eight fired-engine tests and seven bench tests covering all the engine oil parameters. The new bench tests include a seal compatibility test for fresh oils and a low temperature pumpability test for used oils containing 5% soot. This paper provides a review of the all the tests, matrix results, and limits for this new oil category.