xi Input Sensors ..................................................................... 185 On-Off Switches ................................................................ 186 Pressure Sensors ............................................................... 186 Crankshaft Speed and Position Sensors .................... 186 Knock Sensors ................................................................... 188 Temperature Sensors ...................................................... 188 Manifold Absolute Pressure (MAP) Sensor .............. 189 Barometric Pressure Sensor ......................................... 189 Airflow Sensors ................................................................. 189 Oxygen Sensors ................................................................. 190 Throttle Position Sensor ................................................ 191 EGR Position Sensor ........................................................ 191 Other ECM Inputs ............................................................ 191 Output Devices ................................................................. 191 Idle Speed Controls ......................................................... 191 Fuel Injectors ..................................................................... 192 Ignition Coils ..................................................................... 192 Ignition Module ................................................................ 193 EGR System Solenoid ...................................................... 193 Air Injection System ........................................................ 194 Electric Fan Relay ............................................................. 194 Electric Fuel Pump Relay ............................................... 194 Transmission Control Solenoids ................................. 195 X-by-Wire Systems ......................................................... 195 Precautions for Working with Electronic Components .................................. 195 Static Electricity ............................................................... 195 Electromagnetic Interference ...................................... 196 Chapter 10 Ignition Systems . . . . . . . . . . . . . .201 High Voltage Is Necessary ......................................... 201 Primary Circuit ................................................................ 201 Battery ................................................................................. 201 Ignition Switch .................................................................. 203 Resistor................................................................................ 203 Ignition Coil ....................................................................... 203 Methods of Current Interruption ................................ 205 Simple Electronic Ignition............................................. 205 Electronic Triggering Devices ...................................... 206 Distributor Ignition System .......................................... 208 Distributorless Ignition Systems ................................. 208 Primary Circuit Complete ............................................. 211 Spark Plug Construction ................................................ 211 Distributor Cap and Rotor ............................................ 214 Spark Plug Wires .............................................................. 214 Ignition Timing and Advance ................................. 215 Timing Advance Mechanisms ...................................... 216 Chapter 11 Fuel Injection Systems . . . . . . . .221 Providing the Correct Air-Fuel Mixture ........... 221 Fuel Injection ..................................................................... 221 Direct and Indirect Injection ........................................ 222 Mechanical and Electronic Injection ......................... 222 Pulse Fuel Injection ....................................................... 224 Timed and Non-Timed Pulse Fuel Injection ............ 224 Types of Pulse Fuel Injection Systems ....................... 224 Pulse Fuel Injection System Components ...... 226 Air Induction System ...................................................... 226 Fuel Delivery System ....................................................... 226 Cold Start Aids .................................................................. 229 ECM Fuel Control ............................................................ 229 Fuel System Sensors ........................................................ 230 Continuous Fuel Injection Systems .................... 237 Fuel Flow Control ............................................................. 237 Diesel Fuel Injection ..................................................... 237 Diesel Injection Systems ................................................ 238 Chapter 12 Fuel and Air Supply Systems . . .247 Fuels ........................................................................................ 247 Gasoline .............................................................................. 247 Diesel Fuel .......................................................................... 247 Fuel Supply System ........................................................ 248 Fuel Tank ............................................................................ 248 Fuel Pump .......................................................................... 250 Fuel Filter ........................................................................... 253 Fuel Lines ........................................................................... 254 Eliminating Vapor Lock ................................................. 254 Air Supply System ........................................................... 254 Air Cleaners ....................................................................... 254 Throttle Valve .................................................................... 255 Air-Fuel Mixture Heating Systems .............................. 256 Intake Manifolds and Plenums .................................... 258 Superchargers and Turbochargers ...................... 259 Superchargers ................................................................... 260 Turbochargers ................................................................... 260 Boost Control .................................................................... 260 Chapter 13 Cooling Systems . . . . . . . . . . . . . 265 The Need for a Cooling System .............................. 265 Two Methods of Cooling ............................................ 265 Liquid-Cooled Engines ................................................ 266