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Dashpot Control System (1.6L 4A-FE)

  1. Warm engine to normal operating temperature. Ensure idle speed is correct. See IDLE SPEED & MIXTURE in ADJUSTMENTS article.
  2. Remove cover, cap, filter and separator from dashpot. See Fig 1. Install Jumper Wire (SST 09843-18020) between terminals TE1 and E1 of data link connector No. 1. See Figure. Disconnect electrical connector from EGR Vacuum Switching Valve (VSV), located below EGR valve.
  3. Start engine. Maintain engine speed at specified testing RPM. See DASHPOT TESTING SPECIFICATIONS  table.
  4. Plug Vacuum Transmitting Valve (VTV) hole. See Fig 2. Release throttle. Dashpot should be extended and dashpot setting RPM should be as specified. See DASHPOT TESTING SPECIFICATIONS  table.
  5. If dashpot setting RPM is incorrect, rotate dashpot adjusting screw to obtain correct RPM. See Fig 3. Repeat steps 3) and 4) and ensure proper adjustment is obtained.
  6. Reinstall electrical connector on EGR VSV. Remove jumper wire from data link connector No. 1. Install separator, filter, cap and cover. Install filter with coarse surface facing outward (away from dashpot).
  7. To check VTV operation, operate engine at dashpot testing RPM for a few seconds. Release throttle. Ensure engine returns to idle in a few seconds.
Fig 1: Identifying Dashpot (1.6L 4A-FE)
G93E80543Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Fig 2: Identifying Vacuum Transmitting Valve (1.6L 4A-FE)
G93F80544Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Fig 3: Adjusting Dashpot
G93G80545Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
DASHPOT TESTING SPECIFICATIONS

Application Testing RPM (1) Dashpot Setting RPM
1.6L 4A-FE
A/T 3000 2200
M/T 3000 1800
(1) With electric cooling fan off (if equipped).