System Too Lean (P0171, P0174) - Vacuum Leak Quick Test - Ford 5.4

This is a Ford Expedition 5.4 with a vacuum leak causing "System Too Lean" trouble codes P0171 and P0174. In this video I will show you how to use freeze frame data and fuel trim numbers to identify a vacuum leak. Then I will be using water to locate the specific area of the vacuum leak.

Engine Performance Diagnostics chapter 1 pages 9-12

Symptoms:
- rough idle
- poor gas milage
- check engine light (P0171, P0174)
- hesitation
- misfire
- runs better with engine warm

Fix
- replace leaking intake manifold gasket

Tests shown
- how to use freeze frame data to identify the type of lean condition
- how to read and interpret STFT and LTFT numbers
- how to locate a vacuum leak with water
- how to locate a vacuum leak with a smoke machine

Tools used
- global OBD-II scan tool
- water bottle

Playlist
- (Chapter 1) Misfire ID, Compression Tests, Vacuum Leaks, Fuel Trim, Head Gasket, Restricted Exhaust, Low Power, DMM
https://www.youtube.com/playlist?list=PL5E3AEC36DB838BB1

Related videos
- Understanding Short Term and Long Term Fuel Trim (an SD Premium video)
https://youtu.be/oRX2V6_a3dc
- Causes of lean condition trouble codes P0171, P0174 - GM 5 3L
https://youtu.be/3RFTS22w6tM
- P0507 Idle Speed Performance Higher Than Expected (vacuum leak) - Jeep
https://youtu.be/tJgrHkuqcC8
- Ford F-150 P0171 P0174 Trouble Codes - vacuum leak (water test)
https://youtu.be/K-on2hbYUCc
- How to find a vacuum leak with water
https://youtu.be/cuod8-zFSQ4

For more information on this topic, I have written a “field manual” called Engine Performance Diagnostics which is available at www.scannerdanner.com as an eBook or paper book.
Want even more diagnostic training? Whether you are a DIY trying to fix your own car, someone looking to become an auto technician, or a current auto technician that wants to get more into diagnostics, subscribe to ScannerDanner Premium https://www.scannerdanner.com/join-scannerdanner-premium.html There is a 14 day free trial.
On ScannerDanner Premium I will bring you right into my classroom at Rosedale Technical College. You will find page for page lectures taken right from my book as well as exclusive classroom type case studies. What is so special about these classroom case studies? I pull live problem vehicles directly into my classroom and we troubleshoot them in real time, using and applying the theory and testing procedures we learn during the classroom lectures. There is no better on-line training of how to troubleshoot automotive electrical and electronics systems anywhere!

Disclaimer:
Due to factors beyond the control of ScannerDanner LLC, it cannot guarantee against unauthorized modifications of this information, or improper use of this information. ScannerDanner LLC assumes no liability for property damage or injury incurred as a result of any of the information contained in this video. ScannerDanner LLC recommends safe practices when working with power tools, automotive lifts, lifting tools, jack stands, electrical equipment, blunt instruments, chemicals, lubricants, or any other tools or equipment seen or implied in this video. Due to factors beyond the control of ScannerDanner LLC, no information contained in this video shall create any express or implied warranty or guarantee of any particular result. Any injury, damage or loss that may result from improper use of these tools, equipment, or the information contained in this video is the sole responsibility of the user and not ScannerDanner LLC.

Видео System Too Lean (P0171, P0174) - Vacuum Leak Quick Test - Ford 5.4 канала ScannerDanner