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This paper describes the vehicle implementation and cold start calibration of a neat methanol (M100) fuelled port injected engine equipped with plasma jet ignition and prompt exhaust gas recirculation. Test results are presented in which the influence of various factors on fuel enrichment requirements were studied with the aim of identifying strategies to reduce enrichment and lower start-up emissions. Vehicle cold starting has been demonstrated down to -30°C and studied in detail circa -20°C. Reductions in start-up CO emissions at -7°C have been achieved by means of early closed loop fuel control. Experimental results are also presented which indicate that the potential exists to reduce start-up hydrocarbon emissions at 25°C when appropriate calibration strategies are employed.

This paper describes an experimental study in which the potential for fuel economy improvements with EGR was investigated using an automotive V6 engine. Steady state engine dynamometer tests were run at 2000 rpm and 200 kPa Brake Mean Effective Pressure (BMEP). The engine was fuelled with gasoline, methanol or natural gas. Plasma jet ignition was evaluated as a means of improving EGR tolerance. EGR tolerance with methanol was found to be better than with gasoline, while natural gas showed the poorest EGR tolerance. Plasma jet ignition extended EGR limits for all three fuels. Fuel economy benefits were realized with natural gas and gasoline at low EGR rates and without EGR but plasma jet ignition provided no improvements with methanol until over 10% EGR was used. Plasma jet ignition made stable operation possible with methanol at 40% EGR, where fuel economy improvements were ultimately limited by the slow burning associated with the high EGR rate.

Warm-up fuel consumption behaviour as affected by ambient temperature was evaluated for five OEM gasoline fuelled automobiles. Multiple EPA FTP 75 tests were performed with each vehicle at ambient test cell soak temperatures of 25°C and -7°C. Fuel consumption measured during the warm-up (Bag 1, Cold Transient) test segments at these two temperature conditions was compared to the fully warmed Hot Transient (Bag 3) fuel consumption from the 25°C ambient temperature tests (the Bag 1 and Bag 3 segments involve identical speed curves). Fuel consumption increases over the 25°C Bag 3 tests for the two warm-up test conditions were differentiated as those caused by increased drivetrain losses and those caused by intake charge enrichment. Results show wide variations in warm-up behaviour among the five vehicles with respect to the relative increases in fuel consumption, and the proportion of the fuel consumption increases attributable to drivetrain losses and enrichment.