Hard to imagine both oxygen sensors Bank 1 (P2187) and Bank 2 (P2189) failed simultaneously, but that's not to say such is impossible. Recommend rechecking everything prior to (before) the oxygen sensors. Would double check the installation of the K&N intake as well. Driving the car with the two lean codes should be fine for awhile and the engine control module will try to compensate/adjust for the difference. At this point, have not further suggestions and good luck resolving the issue.
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