1979 Models
- Connect a tachometer to engine, then start engine and allow it to reach normal operating temperature. Disconnect servo diaphragm-to-vacuum control valve vacuum hose at vacuum valve and connect it directly to intake manifold vacuum.
- Servo diaphragm is operating properly if engine speed increases to 1650-1850 RPM (1900-2100 RPM on California models) when intake manifold vacuum is applied to servo diaphragm.
- If necessary, adjust servo diaphragm adjusting screw to obtain specified RPM. See Fig 3. Turn adjusting screw clockwise to increase engine speed and counterclockwise to decrease engine speed.