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As part of the P2000 hydrogen fueled internal combustion engine (H2ICE) vehicle program, an engine dynamometer research project was conducted in order to systematically investigate the unique hydrogen related combustion characteristics cited in the literature. These characteristics include pre-ignition, NOx emissions formation and control, volumetric efficiency of gaseous fuel injection and related power density, thermal efficiency, and combustion control. To undertake this study, several dedicated, hydrogen-fueled spark ignition engines (compression ratios: 10, 12.5, 14.5 and 15.3:1) were designed and built. Engine dynamometer development testing was conducted at the Ford Research Laboratory and the University of California at Riverside. This engine dynamometer work also provided the mapping data and control strategy needed to develop the engine in the P2000 vehicle.

The first known, North American OEM vehicle powered exclusively by a hydrogen fueled internal combustion engine (H2ICE) has been developed and tested. This production viable, low cost, low emission vehicle is viewed as a short term driver for the hydrogen fueling infrastructure ultimately required for fuel cell vehicles. This vehicle features a highly optimized hydrogen IC engine, a triple redundant hydrogen safety system, and a dedicated gaseous hydrogen fuel system. The vehicle and its test results are presented in this paper.

Stratified-charge DISI engines have been launched in the market by Mitsubishi, Toyota, and Nissan. This paper discusses the current production stratified-charge DISI systems and some alternative systems, including the system using air-forced fuel injection and a proposed system that uses a swirl flow in the piston bowl with a special shape to separate the fuel-rich mixture layer from the wall surface. New DISI concepts are proposed to overcome some drawbacks of current bowl-in-piston type stratified-charge DISI systems. Charge stratification can be realized by using a soft spray with proper spray penetration, droplet size, and cone angle, as shown by CFD simulation results. The drawbacks of fuel wall wetting, soot limited load with charge stratification, large surface to volume ratio, etc., of the bowl-in-piston type system can be minimized.

Presented in this paper is an on-line method for estimating the oxygen storage capacity contained within a catalyst. The oxygen storage capacity of a catalyst changes over time due to catalyst brick temperatures, poisoned catalyst sites, and thermal aging. Information regarding the current oxygen storage capacity of a catalyst is advantageous in the development of robust emission control strategies and on-board diagnostics. The method of collecting the oxygen storage capacity information is extremely important for measurement accuracy and repeatability. Furthermore, the information must be obtained in such a way that it is transparent to the operator and may be implemented on-line during normal drive cycles. This on-line method for estimation of oxygen storage capacity of a catalyst has been demonstrated on a Ford F150 platform with an underbody catalyst.

The use of methanol as an automotive fuel can be expected to become significant in North America during the 1990's. Methanol fuel will be sold as 85%/15% MeOH/gasoline mixture. Limited availability of methanol fuel in some parts of North America will require methanol vehicles to be dynamically adaptable to fuel compositions ranging from 85% methanol to 100% gasoline. One approach to meeting such a requirement is a sensor that is mounted somewhere in the vehicle's fuel handling system that determines the concentration of methanol in the fuel flowing to the engine. The output of the sensor is supplied to the computer controlled engine management system that sets engine operating parameters. A sensor based on near infrared absorbance is the subject of this paper.

This paper describes two types of dielectric-effect sensors that may be used as alternatives to a dielectric-effect sensor using a single capacitor. In the first type, three capacitors are mounted in a compact module inserted into a vehicle fuel line. The three capacitors are connected together to form an electrical pi-filter network. This approach provides a large variation of output signal as the fuel changes from gasoline to methanol. The sensor can be designed to operate in the 1 to 20 MHz frequency range. The second type of sensor investigated uses a resonant-cavity structure. Ordinarily, sensors based on resonant cavities are useful only if the operating frequency is several hundred MHz or higher. The high relative dielectric constant of methanol allows useful sensors to be built using relatively short lengths of metal tubing for the cavities. For example, a sensor built using a fuel rail only 38.7 cm long operated in a frequency range from 31 to 52 MHz.

Particulate and manganese mass emissions have been measured as a function of mileage for four Escort and four Explorer vehicles using 1) MMT (Methylcyclopentadienyl Manganese Tricarbonyl) added to the gasoline at 1/32 g Mn/gal and 2) gasoline without MMT. The MMT was used in half of the fleet starting at 5,000 miles. The vehicles were driven on public roads at an average speed of 54 mph to accumulate mileage. This report describes the particulate and manganese emissions, plus emissions of four air toxics at 5,000, 20,000, 55,000, 85,000 and 105,000 miles. Four non-regulated emissions were measured and their average values for vehicles without MMT were 0.6 mg/mi for formaldehyde, 0.7 mg/mi for 1,3-butadiene, 9 mg/mi for benzene and 12 mg/mi for toluene. Corresponding values for MMT-fueled vehicles were between 1.5 and 2.4 times higher.

Measurements of oxygen storage capacity (OSC) and HC conversion efficiency for 17 catalysts were carried out in the laboratory. All catalysts with steady state HC efficiency below 90% were found to have roughly equivalent and very low capacities to store oxygen. However, catalyst oxygen storage capacity was seen to rise sharply with HC conversion efficiency in excess of 90 percent. These results parallel the trends which are observed between rear HEGO/EGO indexes for OBD-II catalyst monitoring and HC conversion efficiency. In addition, temperature programed reduction (TPR) was found to lend insight into the relationship between catalyst OSC and HC conversion efficiency by providing a qualitative understanding of the mechanisms by which OSC deteriorates. TPR profiles showed that most of the usable oxygen storage is derived from surface ceria which is interacted with precious metals.

The pneumatic air brake system for heavy commercial trucks is composed by a large number of components, aiming its proper work and compliance with rigorous criteria of vehicular safety. One of those components, present along the whole vehicle, is the air brake tube, ducts which feed valves and reservoirs with compressed air, carrying signals for acting or releasing the brake system. In 2011, due to a lack of butadiene in a global scale, the manufacturing of these tubes was compromised; as this is an important raw material present on the polymer used so far, PA12. This article introduces the methodology of selecting, developing and validating in vehicle an alternative polymer for this application. For this purpose, acceptance criteria have been established through global material specifications, as well as bench tests and vehicular validation requirements.

The fuel effects on HCCI operation in a spark assisted direct injection gasoline engine are assessed. The low load limit has been extended with a pilot fuel injection during the negative valve overlap (NVO) period. The fuel matrix consists of hydrocarbon fuels and various ethanol blends and a butanol blend, plus fuels with added ignition improvers. The hydrocarbon fuels and the butanol blend do not significantly alter the high or the low limits of operation. The HCCI operation appears to be controlled more by the thermal environment than by the fuel properties. For E85, the engine behavior depends on the extent that the heat release from the pilot injected fuel in the NVO period compensates for the evaporative cooling of the fuel.

This article is a new methodology to create a strong and reliable procedure to measure oil level at dealers. Most of time, commercial trucks run full loaded. Engine oil level indication systems are designed to measure oil level at that condition. However commercial trucks are assembled and sold empty and without bodies for trucks. In result of this condition, vehicles with a false indication of low engine oil level are detected at dealers' pre-delivery inspection, resulting in oil addition. This oil addition causes unnecessary costs, since vehicles are produced with maximum oil level. The methodology presented in this study analyzes and treats all variables involved in engine oil level measurements from engine production line until dealers' pre-delivery inspection

In light of forthcoming particle number legislation for light-duty passenger vehicles, time-resolved Particle Mass (PM) and Particle Number (PN) emissions over the New European Drive Cycle (NEDC) are reported for four current vehicle technologies; modern diesel, with and without a Diesel Particulate Filter (DPF), Direct Injection Spark Ignition (DISI) gasoline and multi-point Port Fuel Injection (PFI) gasoline. The PN and PM emissions were ordered (highest to lowest) according to: Non-DPF diesel ≻ DISI ≻ PFI ~ DPF diesel. Both the non-DPF diesel and DISI vehicles emitted PN and PM continuously over the NEDC. This is in contrast with both the DPF diesel and PFI vehicles which emitted nearly all their PN and PM during the first 200 seconds. The PFI result is thought to be a consequence of cold-start mixture preparation whilst several possible explanations are offered for the DPF diesel trend.

A single-cylinder OKP (optimized kinetic process) engine, which uses homogeneous-charge compression-ignition (HCCI) technology, was tested, following a previous study, to evaluate the combustion system robustness and to improve the engine performance near the boundaries of the HCCI operating regime at light loads, high loads and high speed. To evaluate the robustness of HCCI combustion control, gasoline fuels with different RON were used, and the engine was tested at different coolant temperatures. It was demonstrated that the proposed HCCI control approaches could control the OKP engine system to operate robustly using different fuels and at different coolant temperatures. The effects of fuel injection timing and residual gas fraction on HCCI combustion and emissions, especially CO emissions and combustion efficiency, were tested at light loads; and the mechanisms were analyzed.

Automotive three-way catalysts (TWC) were characterized using temperature-programmed reduction (TPR), x-ray diffraction (XRD), Raman spectroscopy, chemisorption measurements and laboratory activity measurements. Capabilities and limitations of these standard analytical techniques for the characterization of production-type automotive catalysts are pointed out. With the exception of chemisorption techniques, all appear to have general utility for analyzing exhaust catalysts. The techniques were used to show that the noble metals and ceria in fresh Pt/Rh and Pd/Rh catalysts are initially highly dispersed and contain a mixture of interacting and non-interacting species. Thermal aging of these catalysts (in the reactor or vehicle) caused both precious metal and ceria particles to sinter, thereby decreasing the interaction between the two.

The objective of this study is to investigate the removal of methane (CH4), nitric oxide (NO), and carbon monoxide (CO) from simulated natural gas vehicle (NGV) exhaust over a palladium catalyst. The effects of changes in space velocity and natural gas sulfur (S) content were studied. The study suggests that the NGV has to be operated slightly rich of stoichiometry to achieve simultaneous removal of the three constituents. The CH4 conversion decreases with an increase in the space velocity. The CO and NO conversions remain unaffected over the space velocity range (10,000 hr-1 to 100,000 hr-1) investigated. The presence of sulfur dioxide in the exhaust lowers the CH4 conversion and increases the CO conversion in the rich region. The NO conversion remains unaffected. Studies were conducted over model catalysts to investigate the modes of CH4 removal from the simulated NGV exhaust.

Recent Federal and California legislation have mandated major improvements in emission control. Tailpipe HC emission must be decreased an order of magnitude for the California Ultra Low Emission Vehicle (ULEV) standard. Present feedback A/F* control systems employ a Heated Exhaust Gas Oxygen sensor (HEGO sensor) upstream of the catalyst to perform A/F feedback control. Limitations on the ultimate accuracy of these switching sensors are well known. To overcome these limitations a linear Universal Exhaust Gas Oxygen sensor (UEGO sensor) placed downstream from the minicatalyst is employed to attain improved A/F control and therefore, higher three-way catalyst (TWC) conversion efficiency. This configuration was granted a patent in 1992 (1**). This study compares performance differences between the two feedback control systems on a Ford Mustang. In initial studies both the UEGO and HEGO sensors were compared at the midposition location downstream of a minicatalyst.

A pressure transducer, closely mounted to the fuel rail pressure regulator of a production fuel system, captured transient waveforms in a bench experiment. Signals were processed to detect the reduction of fuel flow caused by injector clogging. Interference among wave patterns and the proximate action of the pressure regulator made quantitative correlation difficult. However, changes in wave amplitudes can be qualitative indicators of injector clogging problems. A modification was made that moved the regulator nearer the fuel pump outlet and deadheaded the rail. With these modifications, sequential transient pulses from a single operating injector showed good correlation between the pressure drop in the fuel rail during injection and the injector static fuel flow rate. To apply this behavior to multi-cylinder engine analysis, a waveform superposition method was developed to extract single injector information during multi-injector operation.

The effect of MMT on the OBD-II catalyst efficiency monitor has been investigated. The results conclusively show that manganese which is deposited onto the catalyst during the combustion of MMT- containing fuel provides for an increased level of catalyst oxygen storage capacity. This added oxygen storage was found to result in a reduced rear EGO sensor response and caused malfunctioning catalysts to be incorrectly diagnosed by the OBD-II catalyst efficiency monitor.

This paper reviews the design and development of a self-filling, in-tank fuel system reservoir intended for use in diesel engine vehicle applications. This new idea eliminates engine driveability concerns (stumbles, hesitations, stalling, etc.) associated with an inconsistent supply of fuel from the fuel tank to the engine, particularly during sudden vehicle maneuvers and with low fuel tank conditions.

This paper presents the benefits of following a disciplined thermal management process during the design and development of Ford Light Truck engine cooling systems. The thermal management process described has evolved through the increased use of Computer Aided Engineering (CAE) tools. The primary CAE tool used is a numerical simulation technique within the field of Computational Fluid Dynamics (CFD). The paper discusses the need to establish a heat management team, develop a heat management model, construct a three dimensional CFD model to simulate the thermal environment of the engine cooling system, and presents CFD modeling examples of Ford Light Trucks with engine driven cooling fans.