hello, i am having a problem with my regal with its upstream oxygen sensor, i did replace it twice with denso ones, they both read 453 mv on the hp tuners, i cant figure out why they do not oscillate like they are suppose to and with the oxygen sensor not active the car goes into open loop and i can't see fuel trims. i orginally had a problem with the maf and i did swap it out for a working one. on the oxygen sensor its self the white and blue wires are both reading volt, one is 4.5 and the other 5.5. i just double checked the part numbers with denso to make sure i didn't have the wrong part. what kind of reading iam i suppose to be getting from the blue and white wire, i know the black ones are for heater.