Fuel Trim Drivabilty and Emissions

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Across
  1. 2. low fuel pressure would cause long term fuel trim numbers to be_____.
  2. 4. high fuel pressure would cause Long term fuel trim numbers to be______.
  3. 6. normally ranges between 11:1 and 18:1
  4. 7. condition where a sufficient amount of time has passed, engine reaches a predetermined temperature and O2 signal is switching.
  5. 8. acronym for short term fuel trim
  6. 9. This operating condition is used by some manufacturers during cruise speeds where injector pulse width is decreased (A/F ratio is greater than 14.7:1) and O2 sensor readings are monitored but not responded to.
  7. 12. Name for Ideal air/fuel ratio, which is 14.7:1.
  8. 13. control module, responsible for providing maximum power while giving the best possible fuel economy and lowest emissions
  9. 15. this fuel adjustment is from instant feedback from O2 sensor
  10. 16. LTFT starts moving toward STFT when its numbers and STFT numbers are _______.
  11. 17. technician would use LTFT for this instead of STFT.
  12. 18. another name for LTFT, it is a result of driving conditions, mechanical engine wear, driving habits, and environmental conditions
  13. 19. condition indicated by negative fuel trim readings
Down
  1. 1. Unit of measurement for Fuel trim numbers
  2. 3. condition indicated by positive fuel trim readings
  3. 5. memory where Long term fuel trim values are stored.
  4. 10. primary sensor used by PCM to determine A/F ratio
  5. 11. programmed into PCM and are used to determine air/fuel ratios and timing strategy
  6. 14. condition where O2 sensor is ignored and computer relies on onboard calibrations to adjust fuel ratio.