This is the best place to get helpful advice for any Toyota problem one migth be having. My problem started yesterday with the check engine light coming on. I didnt really know what to do...the truck was running fine and not making any sounds. I came home and did a search on Yahoo for Tundra+check engine. The first place online it suggested was Toyota Nation. Just about 99% of answers were involving the O2 sensor. One suggested taking my truck to Advanced auto parts and let them hook my truck up to an electronic code reader. So thats what I did. Sure enough it told the story. O2 sensor was faulty. First thing this morning I called the dealership where I purchased my Tundra and asked if Toyota was having problems with the O2 sensors. The service managers reply was what year is my Tundra and how many miles was on it. I told him 2001 and about 64,000 miles. He said Toyota had extended the warranty on the sensors to 80,000 miles. So It looks as if I'm covered. I came close to buying the sensor from the auto parts store at $128.00 but held out for some warranty hope.