Fund fault code 01-3.Customer already had another tech. Who changed the throttle position sensor. I cheched the spark plugs and found them worn.I replaced them and was able to get the engine started. I switched the oxygen sensor and the engine started better and ran well for an hour then it started to run rough again.The code is still present. Does anyone have any ideas on my next move. Is there a way to clear this code. The truck has a 4y engine. Truck serial #c2783