2010 Yamaha Drive has gone herky/jerky

[LewAshmore]

I've had the cart for 2 years.
It is lifted with oversize tires. All the electrical components appear to be original equipment. About a month ago, we first noticed a minor hesitation when accelerating , but then it would smooth out. This condition continued to increase in frequency and also intensity. Now it jerks forward or doesn't move at all.
I was told it was likely the batteries... Replaced them with 4 12V Trojan T1275.
New batteries did not solve the problem.
Solenoid clicks when switch is toggled from Tow to Run.
Solenoid clicks when key is turned on in Run.
Removed the throttle sensor that is connected to pedal assembly.
When I pulled the sensor, it came out in two parts. The outside casing came apart from the inside components. Physically inspected and there is a little wear where the metal component from the pedal turns the throttle sensor, but it didn't appear to be completely rounded off.
My research on this forum says I should replace the throttle sensor, but also the controller may be bad. I've also read that the stock controller may not be adequate since the cart now has oversized tires and is lifted.
I would appreciate your advise on next steps... Thanks in advance.