Orion

A couple days ago my truck (02 Taco V6 app. 90k miles) suddenly started to run rough when it was at idle. The CEL was not on. So i went home and searched to figure it out. I then changed the fuel filter, spark plugs, and had an injector and throttle body service done. I replaced everything with OEM parts. When i pulled the plugs i checked the wires thoroughly and they looked clean and ok. The plugs i pulled were also ok. This morning i was headed to work and the CEL finally came on with still a rough idle and it feels as if i have also lost a little power. I went and got the code checked and its P0300. Random/Multiple Cylinder Misfire Detected. Has anyone ever thrown this code and know how to fix it? Any advice given is appreciated.