03' F150 SES Light: code P0171
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The code says "System too lean bank 1" The guy at the auto parts store I go to said it could be any one of several things. I just thought that maybe, this being a message board for Ford truck enthusiasts, someone might know a common cause for this so I might have a good place to start.
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What I am trying to do is get you to begin helping yourself to understand what the code is.
Your man at the store was no help.
The code tells you bank one is getting to much air from an air leak. 'Lean'
It is being detected by the OX sensor in the exhaust for that bank. The passenger side.
The code is set because the Long Term Fuel table for that bank has shifted 'rich' trying to account for the excess air.
When the shift gets over 25% the code is set and MIL lamp comes on.
Most of the time the cause is an air leak from faulty rubber hoes or parts in the PCV system.
Check out the hose and fitting from the passenger side valve cover to the rear of the intake manifold where it terminates.
On the back of the intake, you cannot see it very well so feel for softness or other signs of an issue.
I just thought you should know what your working with.
Good luck.
Your man at the store was no help.
The code tells you bank one is getting to much air from an air leak. 'Lean'
It is being detected by the OX sensor in the exhaust for that bank. The passenger side.
The code is set because the Long Term Fuel table for that bank has shifted 'rich' trying to account for the excess air.
When the shift gets over 25% the code is set and MIL lamp comes on.
Most of the time the cause is an air leak from faulty rubber hoes or parts in the PCV system.
Check out the hose and fitting from the passenger side valve cover to the rear of the intake manifold where it terminates.
On the back of the intake, you cannot see it very well so feel for softness or other signs of an issue.
I just thought you should know what your working with.
Good luck.
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