5.4 running lean
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From: Southern California
So much for the Ford diagnostic tree- and don't shoot this messenger either. GRIN!
Hotshot
Joined: Jan 2004
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From: St Louis
For more insight, check out TSB 01-9-7 which includes this excerpt:
F4.) Tips Related to the Fuel System Monitor
- HO2S sensors are not likely to be the cause of adaptive DTCs P0171, P0172, P0174, P0175: Most warranty-returned HO2S sensors (replaced for these DTCs) are found to function normally. Additional related DTCs will normally be present if there is a concern with the HO2S sensors. Do not replace an HO2S sensor unless verified through pinpoint diagnostic tests found in the PC/ED Service Manual.
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From: Southern California
2) be respectful
5th Gear
Joined: Mar 2023
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What do you mean check inputs?
Mike,
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From: Southern California
Check the signal (voltage) to/from the ECM/O2 sensors and then test the O2 sensors themselves (voltage) when they are heated/cooled
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dewalters8886
1999 - 2016 Super Duty
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Mar 20, 2017 04:29 PM
