3 Oxygen Sensors all go bad??

[quote:9261829499="desotomike"]I have a 2000 MR2 Spyder with 63K miles. The check engine light came on and the code showed the O2 sensor for Bank 1 Sensor 1 as NG. I replaced it and then after 15 miles I had the light on again. This time the code showed Bank 1 Sensor 2. I replaced it and after another 20 miles the light was on again. This time it showed Bank 2 sensor 1. Is it normal for all of the sensors to fail one after another?[/quote:9261829499]

Are you using OEM parts-you can try having the exhaust system check for backpressure and the coolant temperature sensor-

Further what are these sensors telling you when you scanned it- Rich/Lean -Low/High voltage?