P2270 (O2 Sensor Signal Stuck Lean Bank1 Sensor2)

[ericsauvage08]

Hello, My 04 XLT (207k mi) has been throwing the P2270 (O2 Sensor Signal Stuck Lean Bank1 Sensor2) for a while. I've replaced all the O2 sensors, the downstream ones twice. I also replaced the PCV (PCV hose looked fine, connections seemed tight) and the Fuel Injection Pressure Sensor. It also has newer plugs, wires, and coil. MAF has been replaced within the last 3 years and still looks ok. Air filter is clean and everything associated with the air intake appears tight. IAT sensor is also newer. Throttle body is clean. Thinking about replacing the EGR (it's original, and rusty) but I am not sure the EGR is directly related to this code. I have read that it could be the cat or an exhaust leak, but am hoping someone has better news for me. Anyone have any ideas? The gas mileage is noticeably worse these days. Thanks!

The following is a readout from the torque app while idling:

Fuel Status = 0 byte
Engine Load = 92.549 %
Engine Coolant Temperature = 195.8 °F
Fuel Trim Bank 1 Short Term = 15.625 %
Fuel Trim Bank 1 Long Term = 7.031 %
Fuel Trim Bank 2 Short Term = 0 %
Fuel Trim Bank 2 Long Term = 10.938 %
Intake Manifold Pressure = 13.779 psi
Engine RPM = 1,963.75 rpm
Speed (OBD) = 61.516 mph
Timing Advance = 16 °
Intake Air Temperature = 87.8 °F
Mass Air Flow Rate = 48.2 g/s
Throttle Position(Manifold) = 34.118 %
Fuel trim bank 1 sensor 1 = 0 %
Fuel trim bank 2 sensor 1 = 0 %
Run time since engine start = 624 s
Fuel Rail Pressure (relative to manifold vacuum) = 38.186 psi
EGR Commanded = 0 %
EGR Error = 0 %
Fuel Level (From Engine ECU) = 34.51 %
Distance travelled since codes cleared = 380.901 miles
Evap System Vapour Pressure = -171.75 Pa
Barometric pressure (from vehicle) = 14.504 psi
Catalyst Temperature (Bank 1,Sensor 1) = 1,346 °F
Catalyst Temperature (Bank 2,Sensor 1) = 1,346 °F
PID: 41 = 0
Voltage (Control Module) = 13.355 V
Engine Load(Absolute) = 60.784 %
Commanded Equivalence Ratio(lambda) = 1
Relative Throttle Position = 20.784 %
Ambient air temp = 73.4 °F
Absolute Throttle Position B = 54.51 %
Accelerator PedalPosition D = 38.039 %
Accelerator PedalPosition E = 43.529 %
Accelerator PedalPosition F = 32.549 %

 

[edcantu9]

Fuel Trim Bank 1 Short Term = 15.625 %
Fuel Trim Bank 1 Long Term = 7.031 %
Fuel Trim Bank 2 Short Term = 0 %
Fuel Trim Bank 2 Long Term = 10.938 %
Intake Manifold Pressure = 13.779 psi

Your engine is running lean. It is adding extra gas to compensate for the vacuum leak you have.

The Fuel trims indicate it is adding extra gas, that is why you are running through gas. The intake manifold pressure should be around 18psi. That means that there is a leak somewhere and it cannot get its normal seal.

Start with simple stuff and check all vacuum hoses, watch youtube videos on how to find a vacuum leak.

And check every where you have replaced parts to make sure everything was done right. It could of been something you did. The more you mess with it, the more chances are that something was done incorrectly.

 

[ericsauvage08]

Thanks for the reply. Since the intake manifold pressure is low, would that indicate an issue somewhere from the throttle body to the air filter - what sensor measures that pressure? Are you aware of any areas to target on the '04s? I'll keep looking, hopefully stumble upon something.

 

[edcantu9]

Thanks for the reply. Since the intake manifold pressure is low, would that indicate an issue somewhere from the throttle body to the air filter - what sensor measures that pressure? Are you aware of any areas to target on the '04s? I'll keep looking, hopefully stumble upon something.

The issue could be anywhere where there is gaskets, vacuum lines, and mating areas of the intake manifold. You could try a smoke smoke machine to find the leak.