The valve has two outputs on one side and one on the downstrea,/vacuum pump side. You should be able to plug one of the two upstream sides, connect mity vac to the other one (leave the downstream side open).

Will this configuration hold vac? If not, that is your problem.

The following attempt at a schematic may only display with non proportional fonts.

Vac pump side door lock side

............................... ____connect vac tester here
.....leave open____/
...............................\____ plug here


Does that make sense....

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