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GS300 & SC300

  1. Warm engine to normal operating temperature. Turn ignition off. Connect timing light to White lead wire at igniter.
  2. Connect scan tool to Data Link Connector (DLC) No. 3. See Figure. Scan tool is used to read engine RPM.
  3. Apply parking brake. Ensure all accessories are off. Place transmission in Neutral. Start engine and maintain engine speed at 2500 RPM for 90 seconds and then allow engine to idle. Ensure idle speed is 650-750 RPM.
  4. Install Jumper Wire (SST 09843-18020) between terminals TC and E1 of DLC No. 1. See Figure. Connector is located near air intake chamber. Check base timing. See IGNITION TIMING  table.
  5. If base timing is correct, go to next step. If base timing is not correct, check for one or more of the following conditions, repair as necessary, then go to next step:
    • Damaged throttle body.
    • Throttle valve is being prevented from fully closing.
    • Throttle position sensor is misadjusted. See THROTTLE POSITION (TP) SENSOR .
    • Valve timing is incorrect (timing belt is incorrectly installed).
  6. Disconnect jumper wire from DLC No. 1. Check controlled timing. Ensure controlled timing is within specification. See IGNITION TIMING  table. If controlled timing is not within specification, problem exists in engine control system.
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