Oxygen Sensor

Any work done in the engine compartment before this happened? Check all vacuum, air cleaner, maf tubing, pcv, make sure all is in good shape, may have to it to dealer or good repair shop, testing of the circuits involved and some of the info needed may be beyond the scope of the driveway mechanic, since you've replaced the sensor and same issue has come up, possibly a circuit issue? Have you put any fuel additives in your tank before this happened? A rarity to be sure, but can affect certain components.