FixVault
Home › Lexus › 1991 › LS 400 › Repair and Diagnosis › Engine Performance › System › Engine Controls - System/Component Tests › Exhaust Gas RECIRCULATION (EGR) › LS400 Vacuum Switching Valve

LS400 Vacuum Switching Valve

  1. Turn engine off. Disconnect vacuum switching valve (VSV) electrical connector. VSV is located in-line between EGR valve and EGR vacuum modulator. Using ohmmeter, check VSV resistance. Resistance should be 33-39 ohms (cold).
  2. Ensure continuity does not exist between each electrical terminal and VSV body. If continuity is present or resistance measurement in step 1) is incorrect, replace EGR VSV.
  3. Identify and disconnect all vacuum hoses from (VSV). Blow air into upper port (near VSV filter). Air should flow freely out of lower port (near VSV electrical connector).
  4. Apply battery voltage and ground to VSV electrical connector. Blow air into upper port. Air should flow out of filter. If air does not flow out of filter, replace EGR VSV.
About FixVault