[blazes9395]

Welcome to AF. You mentioned you have a bad 02 sensor. Has this been looked after? This could very well be the problem.

When you first start it up, like in the morning, does it run alright, take a few seconds,maybe a minute, runs bad, then SES light comes on and it runs alright again? If this is the case could verywell be an O2 sensor. the sensor is not used when the truck is first started, it has to get warmed up, then the system goes into closed loop, and sensor readings are used to control air to fuel ratio. When the O2 sensor is bad, it gives the computer inaccurate readings, the system tries to correct itself, realizes the readings are out of whack, and throws the SES light, and maps predetermined(built-in) values, , using other sensors information also. In this case the truck is still drivable.

DTC P0146 HO2S Insufficient Activity Bank 1 Sensor 3