GMC TERRAIN P0300 P0171 P0141 P0138 MISFIRE FIX/O2 SENSOR REPLACEMENT

In this video i will be going over how to fix the p0300 p0131 p0171 p0141 random misfire/running lean/running rich/low o2 voltage errors and other codes that pop up due to what is most likely a faulty o2 sensor. When you have at least 2 of these codes together it is almost always going to be a bad o2 sensor. See in video for additional codes that may show on your scanner.