The Service Engine Light on my 1998 Land Rover Discovery II came on at around 82,000 miles. I was told that is comes on around this time automatically for the oxygen sensor. I replaced the oxygen sensor, but do not know how to turn off the light. Does anyone know how I can turn off the light without having to take it to a Dealer and spend $90?

 

It doesn't come on automaticly for anything. It only comes on when there is a problem. You need to get the codes read, maybe stop by your favorite auto parts store, they usually do this for free.
Find out what the fault code number is and get back to us. As for turning it off, no can do until the problem is fixed or it will be back on again before you get around the block.
Mike