When checked the contact shows about 125ohms of resistance. Book says it should read zero. Is this an issue. Only takes about 3 or 4 inches of vacuum to activate it. Reads infinite at atmosphere. After some research I see that this hooks to the ignition module and selects the timing curve based on the switch being opened or closed. I would think that the contact being resistive would have adverse affects on this function. Looks like it's time to replace.