York Furnace Won't Ignite Unless Multimeter Attached

I have a York furnace. During the startup cycle, the electric ignitor glows red, but no gas comes out. I can measure 24VAC from the circuit board to the gas pump at the appropriate time. The resistance across the gas pump is infinite. I have another identical furnace where the resistance across the gas pump reads 8 Mohms. So it seems that the gas pump needs to be replaced. (please confirm)

The interesting part is when I leave the wires connected to the gas pump, and stick my multimeter probes (set to VAC) into the connector next to the wires that go to the gas pump as they leave the circuit board. So essentially the multimeter is connected in parallel to the gas pump. I measure the expected 24VAC, and the furnace ignites.

Can anyone explain why the presence of the multimeter makes the gas pump work?

Thanks!