Test One

Start engine and bring to operating temperature (cooling fan comes on). Disconnect vacuum hose from intake manifold. See Fig 1 . Connect a vacuum gauge and check vacuum.

Fig 1: Testing Intake Manifold Vacuum Line
Courtesy of AMERICAN HONDA MOTORS CO., INC.
If no vacuum is present, check vacuum port. If vacuum is present, check vacuum line for proper connections, cracks, blockage or disconnected hose. If vacuum lines are okay, reconnect hose to intake manifold.
Disconnect air suction control solenoid valve connector. See Fig 2 . Using a voltmeter, connect positive probe to Black/Yellow wire terminal and negative probe to Pink wire terminal.

Fig 2: Air Suction Control Solenoid Valve Connector
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Start engine. Check for voltage at idle within 20 seconds after engine start (10 seconds on Coupe). If voltage is present, replace air suction control solenoid valve. If no voltage is present, turn off engine. Remove negative probe from pink terminal and attach to body ground.
Start engine. Check for voltage at idle within 20 seconds after engine start (10 seconds on Coupe). If no voltage is present, repair open circuit in Black/Yellow wire between solenoid valve and fuse. See Figure .
If voltage is present, check for open in Pink wire between solenoid valve and ECU. If wire is okay, See ELECTRONIC CONTROL SYSTEM article in the COMPUTER CONTROLS section.