Remove intake manifold cover. See Figure. Start and warm engine up to normal operating temperature. Shut engine off. Connect scan tool to DLC3. See Figure. Use scan tool to read engine RPM.
Connect timing light lead to Black/Red wire at ignition coil electrical connector on top of front valve cover at cylinder No. 4. See Fig 1. Open wiring harness cover to gain access if necessary. Cylinder No. 4 is second cylinder on left side when viewed from flywheel end of engine. See Figure.
Apply parking brake. Place transaxle in Neutral. Start engine and maintain engine at 2500 RPM for 90 seconds and allow engine to idle. Ensure idle speed is 650-750 RPM.
Install Jumper Wire (SST 09843-18020) between terminals TE1 and E1 on DLC1. See Fig 2. DLC1 is located on end of air intake chamber at passenger's side of engine compartment.
Timing marks are located on timing belt cover, near crankshaft pulley. Ensure base timing is 8-12 degrees BTDC at idle with transaxle in Neutral, and with A/C and all accessories off.
Remove jumper wire from DLC1. 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 Timing Light (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