Auto 165 – Automotive Engine Performance. Chapter 16 Ignition System Components and Operation. OBJECTIVES. After studying Chapter 16, the reader will be able to: Prepare for ASE Engine Performance (A8) certification test content area “B” (Ignition System Diagnosis and Repair).
After studying Chapter 16, the reader will be able to:
Electronic spark timing (EST)
High energy ignition (HEI)
Ignition control (IC)
Ignition control module (ICM)
Iridium spark plugs
Knock sensor (KS)
Magnetic pulse generator
Pickup coil (pulse generator)
Platinum spark plugs
Primary ignition circuit
Secondary ignition circuit
Spark output (SPOUT)
Waste-spark ignitionKEY TERMS
FIGURE 16–2 Typical air-cooled epoxy-filled E coil.IGNITION COILSCOIL CONSTRUCTION
Typical wiring diagram of a V-6 distributorless (direct fire) ignition system.IGNITION CONTROL CIRCUITSBYPASS IGNITION CONTROL
FIGURE 16–29 Running!Ignition timing marks are found on the harmonic balancers that are equipped with distributor ignition.IGNITION TIMINGTHE NEED FOR SPARK ADVANCE
FIGURE 16–30 Running!The initial timing is where the spark plug fires at idle speed. The computer then advances the timing based on engine speed and other factors.IGNITION TIMINGINITIAL TIMING
FIGURE 16–31 Running!A typical waveform from a knock sensor during a spark knock event. This signal is sent to the computer which in turn retards the ignition timing. This timing retard is accomplished by an output command from the computer to either a spark advance control unit or directly to the ignition module.KNOCK SENSORSDIAGNOSING THE KNOCK SENSOR
FIGURE 16–32 Running!Parts of a typical spark plug.SPARK PLUGS
FIGURE 16–33 Running!The heat range of a spark plug is determined by the distance the heat has to flow from the tip to the cylinder head.SPARK PLUGS
1. The primary (low-voltage) ignition system must be working correctly before any spark occurs from a coil. Which component is not in the primary ignition circuit?
2. The ignition module has direct control over the firing of the coil(s) of an EI system. Which component(s) triggers (controls) the module?
3. A reluctor is a ________.
4. HEI, and EIS are examples of ________.
5. Coil polarity is determined by the ________.
6. Because of ________, an ignition coil cannot be fully charged (reach magnetic saturation) until after a delay of about 10 ms.
7. The pulse generator ________.
8. Two technicians are discussing distributor ignition. Technician A says that the pickup coil or optical sensor in the distributor is used to pulse the ignition module (igniter). Technician B says that some distributor ignition systems have the ignition coil inside the distributor cap. Which technician is correct?
9. A waste-spark-type ignition system ________.
10. An ion-sensing ignition system allows the ignition system itself to be able to ________.