Hello,I have mercury 115 efi 4 stroke, serial number: 1B346358My problem is : Engine running normal for few days, I drive it and there is no problem. But every few days when driving at longer distance (more that one-two hour) sometime not always motor dump from normal speed to minimum andI can drive more then 5 knots speed. Something like that he go to safe mode and he change sound of engine. Tomorrow when I start engine he works normal like nothing is happened and I can drive next few days normal. Also before that happen he change speed himself. For example I drive on 3500 rpm and he himself go up speed and down speed. I have Yamaha software and diagnostis show me this : throttle position sensor is not in right position. I take off from engine TPS and test it with ohm-meter and he don’t have dead spots (his range is from 0.16-4.75 /scale 20k ohm/ ). My question is do I need change tps ? do you thing there is problem ? Or you have some better solution.I really don’t know what can be problem( Fuel, sparks, cabels, pumps and other basic stuff is al normal I check It before)
Go to scream and fly website and post this. There are a ton of Mercury guys over there that could help you diagnose this. Could be stator, stator driver, fuel pump or a number of things. Probably not TPS sensor if you're getting good readings.
