Auxiliary Air Valve System
NOTE:
Install tachometer when checking auxiliary air valve system. Ensure tachometer is connected to proper terminals. See IDLE SPEED & MIXTURE in ADJUSTMENTS
article for tachometer connections.
CAUTION:
Some tachometers may not be compatible with ignition system. Consult tachometer manufacturer before connecting tachometer to system. To avoid possible damage to ignitor and/or coil, DO NOT
allow tachometer terminal to become grounded.
- Install tachometer. With engine coolant less than 176°F (80°C), remove air intake hose from throttle body.
- Start engine. Place finger over air valve port to block airflow. See Fig 1. Engine speed should decrease noticeably. Remove finger from air valve port.
- Allow engine to warm to normal operating temperature. Place finger over air valve port to block airflow. Engine speed should not decrease more than 100 RPM.
- If engine RPM does not respond as indicated, check for vacuum leaks or restricted chamber in auxiliary air valve circuit. If no defects are found, replace auxiliary air valve.