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An emissions reduction strategy was developed and demonstrated to significantly reduce cold-start hydrocarbon (HC) and CO emissions from a spark ignition (SI), gasoline-fueled engine. This strategy involved cold-starting the engine with an ultra-fuel rich calibration, while metering near-stoichiometric fractions of air directly into the exhaust ports. Using this approach, exhaust constituents spontaneously ignited at the exhaust ports and burned into the exhaust manifold and exhaust pipe leading to the catalytic converter. The resulting exotherm accelerated catalyst heating and significantly decreased light-off time following a cold-start on the FTP-75 with a Ford Escort equipped with a 1.9L engine. Mass emissions measurements acquired during the first 70 seconds of the FTP-75 revealed total-HC and CO reductions of 68 and 50 percent, respectively, when compared to baseline measurements.

Increased power outputs in high performance diesel engines are being obtained by the use of increased boost pressures obtained from the engine's turbochargers. Reduced compression ratio because of high boost tends to cause cold starting problems and white smoke at idle and light load, especially with a cold engine. One method of alleviating these problems is to make use of glow plugs in the engine cylinders. Applications of glow plugs include a glow plug ignited natural gas engine, methanol DI engine, and IDI and DI diesel engines. This paper describes a glow plug control system that actually controls the glow plug temperature directly. This new control system is better than the systems currently fitted to IDI diesel vehicles. The glow plug controller maintains a constant temperature at the glow plug without the use of any sensor external to the glow plug.