2003 Lexus SC 430FACTORY OEM SERVICE PROCEDURE

Ignition Timing: Lx470

  1. Start and warm engine up to normal operating temperature. Shut engine off. Remove intake manifold cover located on top of engine, battery clamp cover and intake air connector. Connect scan tool to DLC3. See Figure. Use scan tool to read engine RPM.
  2. Connect timing light lead to wire at ignition coil electrical connector on top of driver's side valve cover at cylinder No. 1. See Fig 1. Cylinder No. 1 is front cylinder on left side of engine when viewed from flywheel end of engine. See Figure.
  3. Apply parking brake. Place transmission in Neutral. Start engine and maintain engine 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 on DLC1 located on passenger's side front fender. See Fig 2.
  5. Check timing marks located on timing belt cover, near crankshaft pulley. Ensure base ignition timing is 5-15 degrees BTDC at idle with transmission in Neutral. Shut engine off. Remove jumper wire, timing light and scan tool. Reinstall intake manifold cover, battery clamp cover and intake air connector.
Fig 1: Connecting Timing Light At Ignition Coil (LX470)
G98H11210Courtesy of Β© TOYOTA, LICENSE AGREEMENT TMS1002
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Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
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  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
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