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EGR Vacuum Modulator Check

WARNING: This page does not describe the selected car, but rather 49 other vehicles, including the 2014 Lexus RX 450h, 2014 Lexus GX 460, 2014 Lexus ES 300h, 2014 Lexus CT 200h, and 2013 Lexus RX 450h. However, it is still accessible from the selected car via links, so may be relevant.
  1. Turn engine off. Label and disconnect all vacuum hoses from EGR vacuum modulator. Block ports "P" and "R" with finger (twin ports on side of modulator). Blow air into port "Q" (single port on side of modulator). Air should flow freely out of filter.
  2. Start and run engine at 3500 RPM (ES250 and ES300) or 2500 RPM (GS300 and LS400). Block ports "P" and "R" with finger. Blow air into port "Q". Air should not flow out of filter. If air flows out of filter, replace EGR vacuum modulator.
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