Mercury Villager starting issue

My van starts, but “lopes” before idling smoothly. Only on the 1st start up of the day.

The next time you go to start it, turn the ignition switch to the run position so that the dash lights come on for two seconds, and then turn the ignition switch to off. Repeat this a half dozen times and then try starting the engine. If the engine starts and runs smoothly, there may be a problem with the fuel pump check valve.

Tester