2004 Codes P0171, P0174, P0402, and P2106

[Charlie 2004]

I have P0171, P0174, P0402, and P2106 codes.. Can anyone help me determine what is causing the malfunction codes? Thank you.

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[BluByeU]

PO171 Oxygen Sensor Bank 1 is too lean
PO174 Fuel Injet too lean Bank 2
Both of these codes can come up together indicating a Intake Leak in the Intake Plenum gasket or possibly air filter box not sealed

PO402 code stems from the EGR flow is excessive
PO2106 is triggered by the PCM module when it receives abnormal signals from various componets

Hope this helps

 

[doug7740]

You need to check the freeze frame data to see what code was set first and what the conditions were when it was set. Code P0402, EGR flow excessive detected could cause a lean condition and set the other codes.


If the system is actually running lean and causing the codes to set, the following Technical Service Bulletin should be followed.

doug7740
1955 Thunderbird Blue

 

[Charlie 2004]

You need to check the freeze frame data to see what code was set first and what the conditions were when it was set. Code P0402, EGR flow excessive detected could cause a lean condition and set the other codes.

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If the system is actually running lean and causing the codes to set, the following Technical Service Bulletin should be followed.

doug7740
1955 Thunderbird Blue

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Thank you for this wealth of information. Gives me a lot to consider and check on. I did drive the car after I posted today. Still had the issues. I really looked hard under the hood after I shut it down. May have been a serious vacuum leak on the small hose on the EGR valve. Looks like the mice or rats struck again.