The 2 codes point at the oxygen sensors,
What you should look again is for vacuum leaks - check for failed or loose vacuum lines, leaking intake gaskets, intake air tubes loose or any other source of un-metered air leaks (leaks after the Mass Air Flow Sensor)
2. Restricted fuel filter or bent/pinched fuel system lines (the last one could happens when jacking the car up on fuel line)
3. Incorrect input from other sensors, such as the Mass Air Flow Sensor wiring, which may not always drop a separate code
4. Engine misfire -. You might think that if there is a misfire then you will have all that unburned fuel and it should read rich; right? Well the O2 sensors read only oxygen content in the exhaust, so if you have all that unburned fuel from incomplete combustion then, you guessed it, you also have all that unburned oxygen. High O2 content in exhaust equals a lean reading!
EGR system will typically set a separate code. A leak in the exhaust system before the O2 sensor will also cause incorrect readings. And always check for after- market modifications. These can throw a wrench into the works! The only other possibilities (however unlikely), are wiring issues, computer concerns or a bad O2 sensor.
Friday, March 30th, 2018 AT 1:13 PM