love and rockets

i have alarm 2 beep /1 min and low water pressure at 1 to 2 lb ok
i change sensor to eng 1 to eng 2 and the problem change of engine alarm and pressure
i m sure it s sensor the problem
but i buy two new sensor and the new twice not work it s possible
i have made the same test and samething
anyone have saw that 2 new sensor fail
i have 496 ho
smartcraft
dts