No. 1 Purge Control Valve

Disconnect manifold vacuum hose from manifold. Disconnect and plug control valve-to-water thermo valve hose.
Start engine and run at idle. Blow through manifold vacuum tube. See Fig 1. Air should not pass through control valve.

Fig 1: No. 1 Purge Control Valve Test
Courtesy of MAZDA MOTORS CORP.
Unplug thermo valve hose and reconnect to purge control valve. Blow through manifold hose again. Air should pass through control valve. If valve does not respond as described, replace purge control valve.