Dashpot Control System

Warm engine to normal operating temperature. Ensure idle speed is within specification. See IDLE SPEED & MIXTURE in the ADJUSTMENTS article.
With engine idling, open throttle valve on throttle body until throttle lever separates from end of dashpot. Gradually release throttle valve and note dashpot setting RPM when throttle lever contacts dashpot.
Dashpot setting RPM should be 1900-2500 RPM. If dashpot setting RPM is not within specification, shut engine off. Loosen lock nut and rotate stopper bolt. See Fig 1.
Repeat step 2) until proper adjustment is obtained. Tighten lock nut. To check throttle body Vacuum Transmitting Valve (VTV) operation, operate engine at 3500 RPM. Release throttle. Ensure engine returns to proper idle speed in a few seconds.

Fig 1: Adjusting Typical Stopper Bolt