I brought my 2005 mustang in because the engine light was on and it was reading oxygen sensors. I explained that the engine light was on before with the same reading and I had the oxygen sensors replace at that time, about two weeks previous and then the light came back on so it is not the oxygen sensors. but he insisted it was and put new ones in again and the engine light came right back on saying it was the oxygen sensors. Now i am out all that money and I still have that same problem. Since then I have talked to a Ford dealer mechanic and he explained to me: "It is a one in a million the oxygen sensors will go out. The oxygen sensor is telling you there is something wrong with the motor and most of the time it is a vacuum line".
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