had bank 1 sensor 2 (high), changed rear 02 sensor, ran for two three days, coded the 441 and 137. cleared them, ran two days reappeared with the 420 as additional i just started the motor rolled it up on ramps, go it to operating temperature front of cat was 200-225F , at the rear sensor the temp on the side of the cat was about the same but on top was 300F. I've picked up about 1-2 MPG since o2 change.
Aug 17, 2023 at 2:14 PM
