I've been having trouble with my bike for over a month now. This bike is 100% stock. It was running perfect for the first 13 hours then it miss fired a couple of times and now it will run normal for about 10 minutes then after a short break the rpm meter shows that the bike is idling at 4300 rpm when I know it's about 1/2 that speed. If I Rev the motor the Rev limiter kicks in way to early. I bought a gytr tuner so I could check for any error codes and it shows error code 13. In my manual it tells me to check inlet air pressure sensor and if that is OK replace ECU. I have no way to check the sensor so I was going to replace it but after getting the air box out of the way I discovered that that sensor is screwed to the throttle body with an Allen screw that has a tit in the middle so I'm assuming yamaha doesn't want me messing with it. Should I replace the ECU? What could have caused it to go bad?