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Automotive Service Modern Auto Tech Study Guide Chapter 34
Pages Ignition Systems 42 Points
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Automotive Service 1. The ignition system produces the high voltage needed to _______ the air/fuel mixture in the cylinders. Destroy Ignite Snuff-out
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Automotive Service 2. The ignition system makes electric arcs across the gaps at the _____ ______ and times them to happen exactly as each piston nears TDC of its compression stroke. Spark Plugs Crankshafts Oxygen Sensors
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Automotive Service 3. The 12 volt ______________ is the primary source of electricity for the system but the ignition ________ transforms this voltage into 30,000 or more secondary circuit volts during normal engine operation. Coil, Battery Battery, Coil Starter, Alternator
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Automotive Service 4. The two main circuits in an ignition system are the _________ (low volts) and the ______________ (high volts) circuits. The secondary circuit has thicker insulation to prevent electrical leakage & shorting. Module, Spark Plug Reluctor, Pick-up Coil Primary, Secondary
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Automotive Service 5. The ignition ________ is a pulse-type transformer used to produce short bursts of high voltage for sparks. Module Coil System
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Automotive Service 6. Ignition coils have ________ windings wrapped around __________ windings & a soft iron core or armature in the center of the two windings or coils. Primary, Secondary Secondary, Primary Post-Secondary, Primary
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Automotive Service 7. Primary magnetic ___________ collapsing through secondary coils of wire induce a surge used for spark. Fields Coils Shunts
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Automotive Service 8. Distributorless ignition systems may have one coil pack for every ______ cylinders. A system with one ignition coil for every cylinder is known as a coil-on-plug, coil-near-plug, or a direct ignition system. Two Four Six
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Automotive Service
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Automotive Service 9. On distributorless ignition systems, a coil ________, consisting of several ignition coils combined into one assembly, connects on to the spark plug wires for two cylinders. No secondary coil wire is used in this system. Track Rack Pack
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Automotive Service 10. A ____________ - __________ ignition coil is wired to fire two spark plugs at the same time, one forward polarity (+ to -) & the other reverse polarity (- to +). This is known as the “wasted spark” method. Pick - Up Wasted - Spark Shut - Off
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Automotive Service 11. The ____________________ is used to signal the on/off cycling of primary ignition current, distribute the high voltage secondary current, adjust the timing of the spark, and sometimes even drive the oil pump. Distributor Alternator Starter
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Automotive Service 12. The main switching components inside of an electronic distributor are the _____________ (trigger wheel) & the _______________ coil (a.k.a. sensor assembly or sensor coil). The reluctor & pickup coil are known as a permanent magnet generator. Hall effect & optical pickups are also used to “trigger” the primary circuit. Reluctor & Pick-up Coil Reactor & Pick-up Coil Reluctor & Timer Core
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Automotive Service 13. The primary circuit magnetic fields are building up when the ignition control ____________ is on. This closes the primary circuit. When the primary circuit is opened, the primary fields collapse through the secondary coil winding and fire the spark. Primary circuit closed time is known as “dwell time”. Module Switch Plug
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Automotive Service 14. The ______________________ cap and the __________ are responsible for transferring the high voltage surge from the ignition coil to the spark plug wires in the correct firing order. Distributor & Rotor Distributor & Reluctor Distributor & Coil Pack
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Automotive Service 15. __________ ________ wires are also known as secondary wires since they are the main conductors in the secondary circuit. The abbreviation TVRS on wires stands for television & radio static suppression. Carbon Fiber Spark Plug Primary
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Automotive Service 16. Spark plug wires have between 2, ,000 ohms per foot of resistance to prevent ____________ static. RFI, also known as radio frequency interference Radio MP3 Brain Wave
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Automotive Service 17. The main parts of a spark plug are the
center terminal or __________________, the side or ____________electrode, the ceramic ________________, & the steel shell which ____________ into the cylinder head. Electrode, Ground, Insulator, Threads or Screws Seal, Gap, Ribs, Shell Meat, Potatoes, Coffee, Dessert
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Automotive Service 18. Spark plug thread __________ is the length of the threaded portion of the steel shell. Reach Leach Beach
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Automotive Service 19. Spark plug ______________ are either 14mm or 18mm in diameter and are sealed with either a washer or a tapered seat that fits into the tapered hole in the cylinder head. Gaps Threads Insulators
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Automotive Service 20. A __________________ spark plug has an internal resistance of around 5,000 ohms to 10,000 ohms to reduce RFI. Thermistor Sure Mister Resistor
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Automotive Service 21. Spark plug _________ (distance between the center & side electrodes) is adjusted by bending the side electrode. Gaps Threads Insulators
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Automotive Service Spark plug ________ __________ is
a rating of the ability of the plug to conduct heat away & cool off. Heat Range Thread Reach Part Number
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Automotive Service 23. A hot-running spark plug has a _______ insulator tip and a long path for heat to travel to cool off. Short Medium Long
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Automotive Service 24. A cold-running spark plug has a ______________ insulator tip and a short, quick path for heat to travel. Short Medium Long
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Automotive Service 25. Some engines use two spark plugs per cylinder and some discharge multiple __________ to ignite a/f mix. Sparks Fuels Airs
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Automotive Service 26. Distributor _______________________ advance mechanisms used for power, and ___________________ advance mechanisms used to increase fuel economy, have been replaced by more the reliable, electronic spark control systems. The electronic engine control system now handles spark advance duties. Centrifugal, Vacuum Vacuum, Centrifugal Electronic, Electronic
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Automotive Service 27. Engine ________ monitor various operating conditions & send electrical data to the computer (PCM) where it is analyzed and used to change ignition timing for maximum engine efficiency, performance, mpg, & low emissions. ** These 3 benefits are often referred to as “driveability”. Sparks Sensors Actuators
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Automotive Service 28. Checking the _________ ignition timing is an important tune-up procedure on distributor ignition engines Base Case Lase
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Automotive Service 29. Distributorless ignition systems require less ____________________ and their spark timing is not adjustable. Maintenance Polishing Gasoline
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Automotive Service 30. A _______________ ignition system has an ignition coil mounted over the top of each spark plug. These ignition systems are most often called “coil-on-plug” or “coil-near-plug” systems. Spark plug Boot Ignition coil Cover Direct Dialect Dominant
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Automotive Service 31. Engine ___________ __________ is the sequence in which the spark plugs fire to ignite the a/f mix. Fling Order Firing Order Arrangement
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Automotive Service 32. What are the typical, firing orders that four cylinder engines usually have? ___________ & ____________
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Automotive Service
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Automotive Service
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Automotive Service Distributor Ignition System
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Automotive Service Coil-on-Plug Ignition System also known as Direct Ignition System
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Wasted Spark Ignition System
Automotive Service Wasted Spark Ignition System (Coil Pack)
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Automotive Service
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Automotive Service
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Automotive Service
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Automotive Service The EEC system & the ignition system come together with sensors & the PCM
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