My experience with a failing throttle position sensor is a very bad stumble when cruising at a steadily held speed. A certain rpm sets it off only when HELD at that speed.
My scoot ran flawlessly at idle...max speed....acceleration
...etc. Only stumbled bad at a certain cruise speed.
New throttle body w/TPS fixed it.
2012 KYMCO LIKE200iLX .....BigDam Italian mirrors, 14g Dr Pulley's, Iridium NGK, Yamaha fuel pump, City Grips, lighted Bestem 929, bigger YUASA, TinyTac, seat rebuild
2013 SkyWave AN400