I have been using my 96 to pull the water wagon today. My pump has been hanging up and RPMS will stay at what I had the throttle pedal position at, when going down the road. The only way I can get the RPMS to come back down, is to tap the throttle hard. If I do not do that and push the clutch down, the RPMS will be at 2000-3000 RPMS. I sprayed penetrating oil on all of the throttle linkages and pivot points. I unhooked the throttle and cruise control cables and moved the pump linkage by hand. The pump will hang up and I will have to push the arm in order for the engine to idle. Does this sound like a plunger hanging up or something else?