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Dashpot Control System: M/T

  1. Start and warm engine to normal operating temperature. Ensure idle speed is within specification. See IDLE SPEED & MIXTURE in ADJUSTMENTS - 3.4L article. Shut engine off. Remove cap, filter and separator from dashpot on throttle body. See Fig 1.
  2. Start engine. Maintain engine speed at 2500 RPM. Plug Vacuum Transmitting Valve (VTV) hole in dashpot with your finger. See Fig 2.
  3. Release throttle. Dashpot should be extended and dashpot setting RPM should be 1800-2200 RPM. If dashpot setting RPM is not within specification, rotate dashpot adjusting screw to obtain correct RPM. See Fig 3.
  4. Repeat step 3) to ensure proper adjustment is obtained. To check operation of Vacuum Transmitting Valve (VTV), operate engine at 2500 RPM with finger placed over VTV hole in dashpot.
  5. Release throttle. Remove finger from VTV hole in dashpot. Ensure engine returns to proper idle speed in approximately one second. Install separator, filter and cap. Ensure filter is installed with the coarse surface facing outward (away from dashpot).
Fig 1: Locating Dashpot & Components
G96C09959Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Fig 2: Locating Vacuum Transmitting Valve
G96E09960Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Fig 3: Locating Dashpot Adjusting Screw
G96G09961Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002