Automotive Technology
7th Edition
ISBN: 9781337794213
Author: ERJAVEC, Jack.
Publisher: Cengage,
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Textbook Question
Chapter 30, Problem 2MC
Which of the following statements about fuel trim is not true?
a. A positive fuel trim value means that the PCM detects a lean mixture and is decreasing the pulse width to add more fuel to the mixture.
b. Short-term fuel trim represents changes made immediately in response to HO2S signals.
c. Long-term fuel trim represents changes made to set a new base pulse width.
d. Long-term fuel trim responds to the trends of the short-term fuel trim.
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Chapter 30 Solutions
Automotive Technology
Ch. 30 - Explain the major differences between port fuel...Ch. 30 - What is meant by sequential firing of fuel...Ch. 30 - Explain how the computer controls the air-fuel...Ch. 30 - When the throttle plates are closed in a port...Ch. 30 - If the injector pulse width is increased, the...Ch. 30 - When the engine is idling, the pressure regulator...Ch. 30 - Why are special fuel injectors needed for GDI...Ch. 30 - How does a GDI system provide for a stratified...Ch. 30 - How does a piezoelectric injector work?Ch. 30 - Describe clear flood mode and why it is used.
Ch. 30 - Explain the basic operation of a CSFI system.Ch. 30 - True or False? In GDI systems, the PCM controls...Ch. 30 - True or False? Diesel engines require higher fuel...Ch. 30 - Which of the following statements about fuel trim...Ch. 30 - Which of the following statements about fuel trim...Ch. 30 - While discussing EFI systems: Technician A says...Ch. 30 - While discussing electronic fuel injection...Ch. 30 - While discussing returnless fuel systems:...Ch. 30 - While discussing central port injection systems:...Ch. 30 - While discussing throttle-by-wire systems:...Ch. 30 - While discussing the compression ratios used with...Ch. 30 - While discussing air-fuel ratios: Technician A...Ch. 30 - Technician A says that air-fuel ratios can be...Ch. 30 - While discussing GDI systems: Technician A says...Ch. 30 - While discussing SFI systems: Technician A says...
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