Preparing to Diagnose the Emission and Exhaust Systems . . . . . . . . . . . . . . . . . . . 377 Visual Inspection. . . . . . . . . . . . . . . . . . . . . . . 378 Checking for Excessive Backpressure. . . . . . . . 379 Vacuum Gauge | Exhaust Backpressure Gauge Exhaust Gas Analysis. . . . . . . . . . . . . . . . . . . . 379 Using an Exhaust Gas Analyzer | Understanding Emissions Readings | Comparing Exhaust Analyzer Readings with State Inspection Readings Other Test Equipment. . . . . . . . . . . . . . . . . . . . 381 Performing a Drive Cycle . . . . . . . . . . . . . . . . . 381 Checking Emission Control Components . . . . . 384 Checking the PCV System | Checking Evaporative Emission Control Systems | Checking EGR Valves | Checking the Air Pump and Valves | Checking the Th ermostatic Air Cleaner | Checking Early Fuel Evaporation (EFE) Systems | Checking Emissions Filters | Testing Catalytic Converter Temperature Checking Exhaust System Parts . . . . . . . . . . . . 392 Replacing Emissions and Exhaust Components 393 Evaporative Emissions Canister | Th ermostatic Air Cleaner | EFE Valve | Th ermal Vacuum Valve | EGR Valve | Air Injection System | Exhaust System Components | Catalytic Converters Diesel Particulate Filter Cleaning. . . . . . . . . . . 398 Follow-Up for Emissions and Exhaust Repairs . . . 399 Chapter 19 Engine Mechanical Diagnosis . . . . . . . 403 Diagnosing Engine Problems. . . . . . . . . . . . . . 404 General Inspection | Checking for Vacuum Leaks | Using a Vacuum Gauge | Using an Engine Analyzer to Check Cylinder Vacuum | Checking Engine Compression | Cylinder Leakage Test | Checking the Cooling System | Checking Turbocharger Boost Pressure | Checking Superchargers | Checking Engine Oil Pressure Preparing to Check Internal Engine Components . . . . . . . . . . . . . . . . . . . . . . . . . . 416 Checking Valve Train Parts | Checking Valve Clearance | Checking Valve Lift ers | Checking Camshaft Lobe Lift Engine Service Procedures . . . . . . . . . . . . . . . 420 Repair Th readed Fasteners | Valve Train Adjustment | Fan Clutch Replacement | Electric Cooling Fan and Motor Replacement | Cooling System Th ermostat | Removing and Installing Air Plenums and Intake/Exhaust Manifolds | Replacing Turbochargers | Replacing Superchargers | Replacing Camshaft Drive Components Follow-Up for Engine Repairs. . . . . . . . . . . . . . 431 Chapter 20 Drive Train and Other System Diagnosis . . . . . . . . . . . . 435 Preparing to Check Non-Engine Systems . . . . . 436 Visual Inspection | Noise, Vibration, and Harshness | Eliminating Noise, Vibration, and Harshness Checking Transmissions/Transaxles . . . . . . . . . 437 Checking Manual Clutches | Checking Manual Transmissions/Transaxles | Checking Automatic Transmissions/Transaxles Checking Air Conditioner Operation . . . . . . . . . 445 ECM Controls for the Air Conditioning System | Air Conditioning Low- and High-Pressure Switches Checking Driveline Components . . . . . . . . . . . 447 Checking Suspension and Steering Components . . . . . . . . . . . . . . . . . . . . . . . . . . 448 Checking Wheel, Hub, and Tire Components. . . 449 Checking Brake Problems . . . . . . . . . . . . . . . . 450 Correcting Non-Engine Problems Affecting Driveability . . . . . . . . . . . . . . . . . . . . 450 Adjusting a Manual Clutch | Adjusting an Automatic Transmission/Transaxle Shift Linkage | Replacing a Torque Converter Lockup Clutch Switch | Replacing Transmission/ Transaxle Pressure Switches | Replacing Speed Sensors | Replacing an Air Conditioner Pressure Switch | Driveline Service | Suspension and Steering Service | Brake Service Follow-Up for Drive Train and Other Repairs . . . 456 Chapter 21 ASE Certifi cation . . . . . . . . . . . . . . . . . . 459 ASE Tests. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 460 Other ASE Activities | ASE Test Windows Contents 11