Cat 268B Hydraulic/throttle up problem

I am posting this for a friend who isnt very internet saavy. A customer brought him a 268b skidsteer with an issue of not throttling up. The first story is that cat looked at it and said it needed an injection pump. Going by that this mechanic removed the pump, had it rebuilt and reinstalled. Now the machine idles beautiful, here is the problem. The only way to get the machine to throttle up is to keep the arms or bucket moving. As soon as you stop moving the arms the engine will drop down...

Cat 268B Hydraulic/throttle up problem

Cat 268B Hydraulic/throttle up problem