well a few weeks ago i thought i pulled a code for the front right 02 sensor but never replaced it. i went ahead and reset the ecu and have since been getting more codes but none of them mean anything. should i go ahead and replace the sensor and should this quit tripping the ecu. i already ordered the sensor and was going to install it but the codes lately have been 0505 or no dianosis. also for the replacement of the sensor is the only tool you need a 22mm wrench?