The sensor might be defective, my question now is how does this relate to the pressure being built from tandem pump. for what i understand, with or without the sensor it should lift without rpm, but slowly. Don't you think so, cuz what i notice is that it doesn't lift at all. What I notice also is that I can rev the engine with the directional pedals, forward or reverse it revs up to 2300 rpm, and while revving I pull down the lift lever for the mast to go up but all it does is rev but no movement.

Plus if there is no pressure, the pressure sensor would be useless for it doesn't sense any output pressure.

My apologies if I'm very ignorant but I also see that if there is no pressure the sensor will not work also. I will replace the sensor just to be out of curiosity. any more suggestion?? Thanks