So I posted before how I had replaced my O2 sensor in my '02 4.0l, and then when I came back overseas the check engine came back on. My wife took it to get inspected and they said it was bad needed to be replaced again. Well today she went to the garage and they told her the reason the O2 sensor keeps going is that the radiator is bad. I have never ever heard of a Radiator causing a O2 sensor to go. Never mind this radiator does not leak, is not cracked and the vehicle has never overheated since brand new in 2002. Maybe I am out of the know, has anyone ever heard of a radiator causing the O2 sensor to have problems?