octaneman

Welcome back eliang.

The security light on the truck should be disabled once it starts, but it does not,this leeds me to believe that your no start condition is attributed to GM's pass lock system.There should be a kit available to bypass the security feature on the truck, since you got the truck started, the cam and crank sensors are functioning so you can rule those out. The oxygen sensor though is another matter, the computer detects O2 sensor code affecting the air/fuel mixture. The O2 sensor has to be tested with a DVOM and then inspected for any deposits on it.

Do other electrical systems on the truck like locks, radio, lights, go haywire ?