have codes showing on my 2500HD 01 PO141, 161, 300, 440 any help with what to fix would be great thanks :banghead: :2cents:

po141 = HO2S Heater Circuit Sensor2 Heated oxygen sensors use time to tell if working or not eng not reaching temp fast enuff may set this or bad sensor.
PO161 = ?
PO300 = Engine missfire detected
PO440 = EVAP system fail can be caused by leaving the gas cap lose or a leak in the system
good luck I dont see any one thing to cause all these at the same time.