183 Copyright by Goodheart-Willcox Co., Inc. After studying this chapter, you will be able to: • List the three major pollutants produced by internal combustion engines. • Describe the major types of internal engine modifications designed to control emissions. • Identify the major types of external emission controls. • Explain how emission controls use on-board computer systems. • Describe the purposes of the exhaust system. • Identify the major components of the exhaust system. air-injection-pump system backpressure capless filler neck catalyst monitor catalytic converter diesel exhaust fluid dual exhaust system EGR valve enhanced evaporative emission system evaporative emission control system exhaust gas recirculation (EGR) system exhaust manifold exhaust pipe exhaust system fuel-level sensor header heated oxygen sensor (HO 2 S) hydrocarbons (HC) inspection and maintenance (I/M) program lambda muffler oxides of nitrogen (NO X ) particulate filter PCV monitor PCV valve positive crankcase ventilation (PCV) system pulse-air-injection system resonator selective catalytic reduction system service port soot trap thermostatic air cleaner thermostat monitor three-way catalytic converter valve overlap vent valve Technical Terms Emission Control and Exhaust System Fundamentals Chapter 10