SES light went on my 03 Range Rover HSE. Brought it to the dealer and they said it was the 02 sensor. Paid out of my pocket and got it replaced. Picked up the car. Next day the SES light came back on. Brought it back to the dealer and they said the problem was the Mass Air Flow sensor, which I paid out of pocket and got replaced. That night, after I picked up the car, the SES light went on again. I brought it back to the dealer and they now tell me I have to replace the PCV tubes (vaccum line tubes). Again it will be money out of my pocket. I said no because I think they mis-diagnosed the trouble with the car and made me replace the Mass Air Flow sensor for nothing?