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Home >> Lexus >> 1996 >> LS 400 >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - System/Component Tests >> Emission Systems & Sub-Systems >> Exhaust Gas RECIRCULATION (EGR) System
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Exhaust Gas RECIRCULATION (EGR) System

NOTE: DO NOT  warm the engine until specified. Some testing must be performed when engine is cold.
Fig 1: Identifying Ports On EGR Vacuum Modulator (Typical)
G94D45289Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  1. Ensure coolant temperature is less than 127°F (53°C). Start engine. Shift transmission into Neutral. Block wheels. Connect Jumper Wire (09843-18020) between terminals TE1 and E1 of DLC No. 1. See Figure.
  2. Run engine at 3500 RPM. See CONNECTING TACHOMETER under ENGINE/VIN ID article. Ensure coolant temperature is less than 127°F (53°C).
  3. While engine is running at 3500 RPM, disconnect jumper wire and observe engine RPM. If engine speed remains steady, go to next step. If engine speed does not remain steady, check for faulty EGR system components.
  4. Ensure engine coolant temperature is at least 131°F (55°C). Reconnect jumper wire between terminals TE1 and E1. While engine is running at 3500 RPM, disconnect jumper wire and observe engine RPM. If engine speed increases 100-300 RPM, EGR system is okay. If engine speed does not remain steady, check for faulty EGR system components.