Ezgo 48v electric golf cart goes then slows down

[Limocart]

We have a 2006 ezgo shuttle/limo golf cart we have a fairly new controller and a brand new admiral motor. We blew the last motor up and the controller was connected to that motor. We ordered a new admiral motor motb2 we hooked it up and the cart will run full speed for a second then slow down to about 1mph. We replaced the solonoid speed sensor and the controller is flashing a 1,3 code what else can be wrong with this thang? We have a sepex 1264 -400amp controller we are out of ideas we have tried to reset the controller but we get no reverse beeps when doing that. Please HELP!!!

[Limocart]

Ok if anyone else has this problem. We called the company we got the motor from they are saying the speed sensor is bad which can also mean the magnet in the motor. Therefor the motor is BAD they are sending us a new one!