Ironeagle

I parked my 2018 Massimo MSU500 in a clean shop for two weeks. When I brought it out for routine ranch work it started cutting out at 18MPH. It's not the seatbelt safety switch, if the belt is not buckled that engages at 10 MPH. I replaced the ECU, fuel injector, coil, plug wire and spark plug. No error code is presented. I put the original ECU back in and reset it then adjusted the idle to 1800 rpm. I don't mind replacing faulty components but don't want to blindly parts chase hoping for the best. Does anyone have experience with a similar situation??

My 2018 Massimo MSU 500 was operating just fine. I parked it for 2 weeks in my shop now the unit starts and runs great but at 18 MPH it cuts out. It's not the seatbelt safety switch that engages at 10 MPH if it is unbuckled. I purchased a new ECU but that did not resolve the problem. No error code is presented. I reset the ECU replaced the fuel injector, coil, sparkplug and spark plug wire. Same response. I don't mind replacing faulty components but don't want to chase parts and hope for the best. Any ideas??