Toyota Repair: CHECK ENGINE LIGHT, oxygen sensors, highway trips

Question
I recently bought a 2000 Tundra 2wd, A/T w/27400 miles.It has a 4.7 liter V8.It was garage kept and only used on highway trips to tow a boat.Ive had it for 2 months and use it on a daily basis,and yesterday the check engine light came on.I know theres probably 10,000 reasons why it could have I just thought maybe you could tell me some things I could check myself.

Answer
The two most common check engine light issues on these are the oxygen sensors(o2 sensors)and emission control evap system failures unfortunately you can't check them yourself because it takes a diagnostic scantool to retreive the trouble code that identifies the problem. The one thing that you can check is that the gas cap is on and tight, if not, it will make the light come on.