when you fit the new one make sure these are no blockages in the rubber hoses that lead from the sensor.
To remove the hoses use a small pick or very thin screwdriver to prise a little of the hose away from the plastic part of the sensor and spray some wd40 into the gap, twist the hose a little and it will come off easily. if you just try and pull it the inside of the hose will stay on the sensor and the outside sheath will come away.