Automotive Service Modern Auto Tech Study Guide Chapters

Automotive Service Modern Auto Tech Study Guide Chapters 43 & 44 Pages 803 - 857 Emission Control Systems 40 Points

Automotive Service 1. Emission control systems are used on vehicles to reduce the amount of ___________ released into the atmosphere. On >1996 vehicles in Wisconsin the VIP mandates a yearly IM-240 test. Harmful Chemicals Beneficial Chemicals Inert Substances

Automotive Service 2. Federal laws to reduce air pollution are enforced by the _________. NRA EPA ASPCA

Automotive Service 3. Airborne pollutants combined with O 2 & N in sunlight produce yellow-gray, photochemical _____. Grog Smog Fog

Automotive Service 4. _______ (HC) are an emission of unburned fuel. (a misfire in a cylinder leads to HC pollution) Nitrocarbons Hydrocarbons Monoxocarbons

Automotive Service 5. HC pollution is formed by either INCOMPLETE combustion or by escaping fuel VAPORS.

Automotive Service 6. __________ (CO) is caused by fuel burning with a lack of oxygen. It is a colorless, odorless, and deadly poisonous gas. Anything that richens the air/fuel mixture increases CO formation. Carbon Dioxide Carbon Tetrachloride Carbon Monoxide

Automotive Service 7. _____ of _____ (NOx) are caused by extremely high temperatures (> 2500 F°) and extremely high pressures from spark knock during combustion. Oxides of Nitrogen Oxides of Hydrogen Oxides of Carbon

Automotive Service 8. ____ are solid particles of carbon, soot & fuel additives that are emitted with exhaust. Perchlorates Particulates Partitions

Automotive Service 9. _____% of vehicle emissions come from engine exhaust, _____% from blow-by gases, and _____% from evaporation of fuel. The PCV controls crankcase blow-by emissions. The EVAP system controls evaporative emissions. Richer = Less Air than Stoichiometric Leaner = More Air than Stoichiometric

Automotive Service 10 -15. Many devices and systems have been developed to limit emissions. Electronic Engine Control & EFI systems in general along with the following six specific systems have been the most successful: remedy systems CAT AIR PCV prevent systems TAC EVAP EGR pollutants controlled HC/CO/NOx HC & CO pollutants controlled HC & CO HC NOx Catalytic Converter Air Injection System (also known as Secondary Air) Positive Crankcase Ventilation Thermostatic Air Cleaner Evaporative Emission Controls Exhaust Gas Recirculation

Automotive Service 16. The ______ is the main component in the Positive Crankcase Ventilation system.

Automotive Service 17. Besides the non-vented fuel tank cap, the charcoal or carbon ______ are the main parts of the EVAP system. PCM-controlled purge valves allow burning of captured vapors at the proper time.

Automotive Service 18. The ______ valve allows unburnable (inert) exhaust gases to enter the combustion chamber so that peak burning temperatures are reduced. This lowers the formation of NOx pollution. EGR is PCM controlled. Exhaust Gas Recirculation Valve EGR “Cools the Burn”

Automotive Service 19. The ___________ is a belt-driven device that forces low pressure, fresh air into the exhaust stream to oxidize HC & CO emissions. Some air pumps are now electrically driven. Air Injection Pump Air Detection Pump Air Rejection Pump

Automotive Service 20. _______ valves in the AIR system prevent backfire during deceleration.

Automotive Service 21. AIR _____ valves in the air distribution manifold prevent exhaust gases from backing up into the air injection pump & hoses. Check Valve Gulp Valve Diverter Valve

Automotive Service 22. The thermostatic air cleaner system uses a thermal _______ valve and a ______ motor to control the heat control door on the air cleaner assembly. If incoming air can be kept between 85º-125º F then HC and CO pollution will be reduced during engine warm-up and cold weather operation. Vacuum, Vacuum Pressure, Pressure Electric, Electric

Automotive Service 22. The thermostatic air cleaner system uses a thermal _______ valve and a ______ motor to control the heat control door on the air cleaner assembly. If incoming air can be kept between 85º-125º F then HC and CO pollution will be reduced during engine warm-up and cold weather operation. Vacuum, Vacuum Pressure, Pressure Electric, Electric

Automotive Service 22. The thermostatic air cleaner system uses a thermal _______ valve and a ______ motor to control the heat control door on the air cleaner assembly. If incoming air can be kept between 85º-125º F then HC and CO pollution will be reduced during engine warm-up and cold weather operation. Vacuum, Vacuum Pressure, Pressure Electric, Electric

Automotive Service 23. _____ AIR systems accomplish the same thing as the regular AIR system, but without an air pump. Pulse Pressure Vacuum Pulse Air aka. Pair

Automotive Service 24. A ________ is any substance that speeds up or promotes a chemical reaction. The catalyst materials in a CAT are coatings over a heat-resistant ceramic monolith or honeycomb substrate. Catalyst Inert Reactor

Automotive Service 25. The ________ works at about 1400 Fº to oxidize HC & CO and to reduce or deoxidize NOx emissions.

Automotive Service 26. _______ and ________ are the oxidation catalysts for HC and CO in a CAT. Platinum & Palladium Titanium & Kryptonite Zirconium & Rhodium

Automotive Service 27. ________ is the reduction catalyst for NOx in a CAT. Rhodium Zirconium Titanium

Automotive Service 28. The ________ ______ (PCM) is an integral part of emission control systems on vehicles since many systems need precise electronic controlling to be effective. Powertrain Control Module Powerful Control Monitor Powertrain Comfort Module

Automotive Service 29. OBD II electronic engine control systems use 2 _________ sensors (EGOS or (HO 2 S). Energy Glow Oxides Exhaust Gas Oxygen Exhaust Going Out

Automotive Service 30. An upstream (pre-CAT) EGOS made with ________ and platinum is used to monitor engine efficiency. The upstream EGOS is the main determining sensor for closed loop air/fuel mixture control. Rhodium Zirconium Titanium

Automotive Service 30. An upstream (pre-CAT) EGOS made with ________ and platinum is used to monitor engine efficiency. The upstream EGOS is the main determining sensor for closed loop air/fuel mixture control. Rhodium Zirconium Titanium

Automotive Service 31. A downstream (post-CAT) EGOS is used as a CATALYST monitor, checking CAT efficiency…”How well exhaust gases are being cleaned up”

~~~ Automotive Service 32. OBD II systems monitor engine ______ and will turn off injectors on malfunctioning cylinders. (8 OBD II Monitors or Self-Tests) Campfire Re-fire Misfire

Automotive Service 33. An exhaust gas ______ is used to measure the chemical content of the engine’s exhaust gases. Scanner Analyzer Digester

Automotive Service 34. The best exhaust gas analyzers monitor all ___ gases… (HC/CO/CO 2/ NOx). 3 5 7

Automotive Service 35. ______ is the Inspection & Maintenance test that lasts for 240 seconds of driving on a chassis dynamometer while exhaust gases are measured. The WI VIP uses this test before registration of vehicles.

Automotive Service 36. The Vehicle _______________ (VECI) sticker located under the hood provides engine and emission control system data and other tune-up & performance related specifications.

Automotive Service Fuel Tank Cap Pressure Tester Diagnostic Smoke Machine Leaky Fuel Tank Caps Cause HC Evaporative Emissions

Automotive Service

ABS SRS HVAC Chassis Sensors Upstream (A/F) & Downstream (CAT) Inputs Anti-Theft Body ECT PROM & RAM MIL Engine MAP CKP CMP P/N Outputs Actuators Ignition Spark IAT MAF DTC’s DLC PCM HO 2 S TPS Scan Tool EFI (injectors & IAC) Open Loop Mode Closed Loop Mode Clear Flood Mode Limp-In Mode Emission Controls (6 CAT – AIR – PCV TAC – EVAP – EGR Cruise Accessories Instrument Cluster KS VSS Electronic Engine Control System Block Diagram

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Automotive Service Catalytic Converter Efficiency

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