I went to AutoZone today to have them pull the codes from my computer to find out why the check engine light is staying on (been on for a few weeks now). We got a 154, 173, and 1151.
154 says "O2 Sensor Circ.,Bank2-Sensor1 No Activity Detected"173 says "Fuel Trim,Bank2 Malfunction"
1151 says "Lack Of HO2S21 Switches - Sensor Indicates Lean"Do these three codes indicate that the upstream sensor on the driver's side needs to be replaced? Has anyone had similar codes and it turned out to be something other than an O2 sensor? I'm just wondering if I should bother doing any further diagnosis or if I should just buy the new sensor ($59 from AutoZone). The truck has 99,900 miles on it but I've only owned it since 84k so I don't know if they've ever been replaced.
Thanks for your help, Dave Earle