my o2 sensor has been out for about 2 years hahah

 

your truck has 4 o2 sensors, 2 on each bank with 4 cats as well, also 2 on each bank. 2 smaller pre-cats which are located closer to the manifold for cold-starts (they warm up and start working quicker) and the 2 cats that you see in the most obvious place before the y-pipe. there are 2 o2 sensors up near the manifold that are used to determine the air/fuel ratio AFTER combustion. these are the crucial ones. if one of these is malfunctioning, it may cause rough running, poor mileage, etc. however, if one of the o2 sensors that are AFTER the cats, called "CAT efficiency" sensors, are detecting a bad reading, you don't need to worry, necessarily, if it's driving fine. so, i think you're golden... just keep driving, haha. but most definitely get your codes read. and if you want to get rid of the code, change the sensor and check all the wires to make sure none of them have melted. they are usually in a protective sleeve but who knows, it could happen. i hope this info helps you out.

 

wow thanks i am getting it fixed in the spring go it is off i hate the look on the dash then i have the check engine for if somthing else goes