Remove intake manifold cover. See Figure. Start engine and warm engine to normal operating temperature. Shut engine off. Connect scan tool to data link connector No. 3. See Fig 1. Scan tool is used to read engine RPM.
Connect timing light lead to lead wire located near ignition on top of front valve cover. See Fig 2.
Apply parking brake. Place transaxle 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.
Install Jumper Wire (SST 09843-18020) between terminals TEI and E1 on data link connector No. 1. See Fig 3. Data link connector No. 1 is located just in front of driver's side strut tower.
Timing marks are located on timing belt cover, near crankshaft pulley. Ensure base ignition timing is 8-12 degrees BTDC at idle with transaxle in Neutral, and with A/C and all accessories off. Remove jumper wire from data link connector No. 1. Ensure ECM controlled timing is 10-25 degrees BTDC. Shut engine off. Remove timing light and scan tool. Reinstall intake manifold cover.

Fig 1: Connecting Scan Tool To Data Link Connector No. 3 (RX300)

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.

• Brakes feel soft, pull hard to one side, or make grinding noises.

• The engine overheats, stalls repeatedly, or misfires under load.

• You are missing required tools, torque specs, or safe lifting equipment.

• You are not confident in the next step or safety outcome.

Safety Warning

Ignition Timing: RX300