I brought my car today to my local Toyota dealer for service after observing the "Check Engine" light illuminating a couple of days ago. The technician diagnosed the problem and replaced an Air Fuel sensor. I think this is also called an Oxygen sensor. This turned off the light, but I was advised that I should have the Cam Seals replaced soon as Oil was found to be seeping through. In addition, he suggested that the Timing belt also be replaced as it is located in the same area and it would save on labor since the same components would have to be disassembled.
Are Cam Seals a common part failure? I've had the oil changed regularly (3 months/3000 miles) and the car has not been driven hard.
Thank you for any advice/comments.