1979 Models
- Disconnect throttle opener control solenoid electrical connector. Connect a vacuum gauge to intake manifold vacuum to check operating pressure. Start engine and allow it to reach normal operating temperature. Check and adjust engine idle speed.
- Run engine under no load and note operating pressure shown on vacuum gauge. Increase engine speed to 3000-3500 RPM, quickly close throttle valve, and note vacuum gauge reading.
- Manifold vacuum should quickly increase to at least 24 in. Hg, then gradually decrease to level noted at idle. Operating pressure (vacuum) at idle should be as specified in THROTTLE OPENER OPERATING PRESSURE table.
- If necessary, turn adjusting nut on end of vacuum control valve clockwise to increase pressure and counterclockwise to decrease pressure. See Figure.
NOTE:
When adjusting throttle opener operating pressure, turn adjusting nut in or out with lock spring in place. Always set lock spring properly to prevent changes in pressure.
THROTTLE OPENER OPERATING PRESSURE
| Application | Vacuum (In. Hg) | |
|---|---|---|
| All Models | ||
| Federal | 19-21 | |
| Calif | 21-23 | |