Engine performance Exam 2 Questions and Answers Rated A

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Engine performance Exam 2 Questions and Answers Rated A The primary (low-voltage) ignition system must be working correctly before any spark occurs from a coil. Which component is NOT in the primar ... y ignition circuit? ✔✔Spark plug wiring A reluctor is a ________. ✔✔Notched ring or pointed wheel The ignition module has direct control over the firing of the coil(s) of an EI system. Which component(s) triggers (controls) the module? ✔✔Pick up coil HEI and EIS are examples of ________. ✔✔Distributor ignition systems Coil polarity is determined by the ________. ✔✔Direction of rotation of the coil windings Because of ________, an ignition coil cannot be fully charged (reach magnetic saturation) until after a delay of about 10 ms. ✔✔Inductive reactance The pulse generator ________ ✔✔Signals the computer that fires the spark plug directly 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? ✔✔Both tech distributor ignition A waste-spark-type ignition system ________. ✔✔Fires one spark lug with reverse polarity Fires one spark plug with straight polarity Fires two spark plugs at the same time An ion-sensing ignition system allows the ignition system itself to be able to ________. ✔✔Detect rich or lean air-fuel mixture Detect spark knock Detect misfire Technician A says that a defective crankshaft position sensor can cause a no-spark condition. Technician B says that a faulty ignition control module can cause a no-spark condition. Which technician is correct? ✔✔Both tech no-spark condtion Most ignition systems work by switching the circuit grounding the ignition coil's primary windings. ✔✔True Which term describes the principle used to create high voltage from low voltage? ✔✔Electromagnetic induction Technician A says that the primary and secondary ignition systems are never connected. Technician B says that the primary and secondary windings are connected in some ignition coils. Which technician is correct? ✔✔Tech B ignition coils Technician A says that the primary coil has more windings. Technician B says that the secondary coil has more windings. Which technician is correct? ✔✔Tech B secondary had more coils Turning off the low voltage primary coil induces a high voltage in the secondary windings. ✔✔True The primary coil windings are designed for higher current (2-6 Amperes). ✔✔TrUe What is the name of the electronic component inside the ignition module that opens and closes the primary ignition circuit? ✔✔Tansistor Which switching device uses a shutter blade and sensor to detect a magnetic field? ✔✔Halleffect switch Which switching device uses LEDs? ✔✔Optical sensor Technician A looks for engine speed (RPM) when cranking an engine that will not start. Technician B says that a problem in the primary circuit could make the tachometer not work. Which technician is correct? ✔✔Neither Tech tachometer Which switching device creates its own electrical voltage pulse? ✔✔Pickup coil How many ignition coils should you expect to find on a V6 engine using a waste spark system? ✔✔Three Technician A says that ignition timing cannot be adjusted on waste spark ignition systems. Technician B says that most waste spark systems use a crankshaft position sensor. Which technician is correct? ✔✔Both techs waste spark Coil-on-plug ignition systems have which of the following advantages over waste spark systems? ✔✔Reduces electromagnetic interference The ________ sends a pulse signal to an electronic ignition module. ✔✔Pickup coil Typical secondary coil resistance specifications usually range from ________ ohms. ✔✔6,000 to 30,000 Typical primary coil resistance specifications usually range from ________ ohms. ✔✔1 to 3 Technician A says to check for spark from the ignition coil first when diagnosing a no-start condition. Technician B says to check the engine CAM sensor first to diagnose a no-spark condition. Which technician is correct? ✔✔Tech A no-start condition Technician A says to use a normal spark plug when checking for spark. Technician B says that a spark tester should be used to check for spark. Which technician is correct? ✔✔Tech B spark tester Testing an ignition coil for resistance will always indicate its condition. ✔✔False Ignition systems may be disabled by removing the secondary wire from the ignition coil. ✔✔FaLse Engine speed and position sensors only affect the ignition system. ✔✔FALSE Technician A says that platinum tipped spark plugs should never be re-gapped after using in a running engine. Technician B says that spark plugs should not be removed from a hot cylinder head. Which technician is correct? ✔✔Both tech pltinum tips Which of the following would cause carbon fouled spark plugs? ✔✔Rich fuel mixture Which of the following could cause oil fouled spark plugs? ✔✔Defective valve stem seals Which type of safety device will keep the electric fuel pump from operating if it is tripped? ✔✔Inertia switch Fuel lines are constructed from ________. ✔✔Seamless steel tubing Nylon plastic What prevents the fuel pump inside the fuel tank from catching the gasoline on fire? ✔✔No air is around the motor brushes A good fuel pump should be able to supply how much fuel per minute? ✔✔0.6 to 0.8 gallons Technician A says that fuel pump modules are spring-loaded so that they can be compressed to fit into the opening. Technician B says that they are spring-loaded to allow for expansion and contraction of plastic fuel tanks. Which technician is correct? ✔✔Tech B spring-loaded Most fuel filters are designed to remove particles larger than ________. ✔✔20 microns A fuel pump is being replaced for the third time. Technician A says that the gasoline could be contaminated. Technician B says that wiring to the pump could be corroded. Which technician is correct? ✔✔Tech B Fuel pump replacement A fuel filter has been accidentally installed backwards. What is the most likely result? ✔✔Lower power at higher engine speeds and loads Technician A says that fuel tanks on 1993 and later vehicles use a check ball to prevent siphoning gasoline through the filler neck. Technician B says that methanol is considered a poison. Which technician is correct? ✔✔Both 1993 The fuel pickup tube is part of the filler tube assembly ✔✔False tube assembly Inline fuel filters may be installed either direction ✔✔False inline fuel filters What happens when fuel lines get too hot and only fuel vapors go through the fuel injectors? ✔✔Vapor lock Technician A says low power on acceleration is a symptom of a restricted fuel filter. Technician B says loss of high speed engine performance is a symptom of a restricted fuel filter. Which technician is correct? ✔✔Both restricted fuel filter On a most cars how long will the fuel pump run if the ignition is turned on but the engine is not started? ✔✔Two seconds Why are some fuel rails rectangular in shape? ✔✔Reduces noise Which fuel-injection system uses the MAP sensor as the primary sensor to determine the base pulse width? ✔✔Speed density Why is a vacuum line attached to a fuel-pressure regulator on many port-fuel-injected engines? ✔✔To create an equal pressure drop across the injectors Which sensor has the greatest influence on injector pulse width besides the MAF sensor? ✔✔TP Technician A says that the port fuel injection injectors operate using five volts from the computer. Technician B says that sequential fuel injectors all use a different wire color on the injectors. Which technician is correct? ✔✔Tech B Injectors Which type of port fuel-injection system uses a fuel temperature and/or fuel-pressure sensor? ✔✔Electronic returnless systems Dampeners are used on some fuel rails to ________. ✔✔Reduce noise Where is the fuel-pressure regulator located on a vacuum-biased port fuel-injection system? ✔✔At the outlet of the fuel rail Technician A says that most fuel injection systems use the PCM to control the pulsing of the fuel injectors. Technician B says that most fuel injection systems use the PCM to control the operation of the fuel pump relay. Which technician is correct? ✔✔Both Techs PCM Which term describes the PCM shutting off fuel injection when the accelerator is pressed all the way down? ✔✔clear flood mode Which term describes the PCM using oxygen sensor feedback to control fuel delivery? ✔✔Closed loop mode Where is the fuel injected in an engine equipped with gasoline direct injection? ✔✔Directly into the combustion chamber The fuel pump inside the fuel tank on a vehicle equipped with gasoline direct injection produces about what fuel pressure? ✔✔50 to 60 psi The high pressure fuel pumps used in gasoline direct injection (GDI) systems are powered by ________. ✔✔The camshaft The high pressure fuel pressure is regulated by using ________. ✔✔An electric pressure control valve The fuel injectors on a GDI engine operate under a fuel pressure of about ________. ✔✔500 to 2,900 psi The fuel injectors used on a gasoline direct injection system are pulsed on using what voltage? ✔✔50 to 90 volts Some engines that use a gasoline direct injection system also have port injection. ✔✔True gas direct injection A gasoline direct injection system can be used to start an engine without the need for a starter motor. ✔✔True A lack of power from an engine equipped with gasoline direct injection could be due to ________. ✔✔Noisy injectors Carbon on the intake valves When compared to conventional port fuel injection, a GDI equipped engine has a ________ compression ratio. ✔✔higher At idle the injector pulse width of a GDI injector is about ________. ✔✔0.4 ms Technician A says that the cylinder head and piston design of a GDI engine is the same as in a port injected engine. Technician B says that a GDI engine uses specially shaped pistons. Which technician is correct? ✔✔Tech be GDI engines A characteristic of GDI systems that could cause a customer concern is ________. ✔✔The high fuel pressure causes the injectors to be noisy The high pressure fuel pump is cooled by ________. ✔✔The fuel itself In a GDI engine the tank fuel pump delivers fuel to ________. ✔✔High pressure pump [Show More]

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