Engine Performance ASE A8 Review Questions with Answers

What are the key components in an EVAP system? Fuel Tank, gas cap, lines/hoses, and charcoal canister Catalytic Converter: Oxidizes NOx into CO and HC When testing a connector what is an acceptable reading? a.) 1V from ground side b.) 1V from positive/reference side c.) .5V from at each connector d.) 1.5v from sensor harness C An oxygen sensor is reading 400mv, what would this indicate lean condition What increases NOx emissions? High combustion temperatures You have examined a set of spark plugs and found them to have a black crusty finish on them. What does this indicate? Rich air/fuel mixture A vehicle comes in with poor performance, low power and a flashing check engine light. What would this indicate? Engine misfire What is the function of the EGR valve? to recirculate exhaust gases into the intake Emission control systems are installed on engines to reduce what 3 specific exhaust emissions? (HC) hydrocarbons, (CO) Carbon Monoxide, and Oxides of Nitrogen (NOx) You are monitoring the TPS/APP sensor voltage reading with slow steady acceleration should read: .50v at idle to 4.5 at WOT If the voltage reading on one cylinder is not high enough, what is the most likely source of the problem? Bad spark plug At WOT the PCM module reverts to: Open loop, rich mixture What are the 2 types of EVAP Leaks? 0.020 small leak and 0.040 large leak 1.) All the following are pre-combustion emission controls except: a.) Catalytic converter b.) PCV system c.) Timing control systems d.) EGR systems A