Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Ignition Timing Inspection
- Connect the HDS to the DLC (see step 2 on GENERAL TROUBLESHOOTING INFORMATION ).
- Turn the ignition switch to ON (II).
- Make sure the HDS communicates with the vehicle and the PCM. If it does not communicate, troubleshoot the DLC circuit (see DLC CIRCUIT TROUBLESHOOTING ).
- Check for DTCs (see GENERAL TROUBLESHOOTING INFORMATION ). If a DTC is present, diagnose and repair the cause before continuing with this test.
- Start the engine. Hold the engine speed at 3, 000 rpm with no load (in P or N) until the radiator fan comes on, then let it idle.
- Check the idle speed (see IDLE SPEED INSPECTION ).
- Jump the SCS line with the HDS.
- Connect the timing light to the exhaust side No. 1 ignition coil harness.
- Aim the light toward the pointer (A) on the cam chain case. Check the ignition timing under no load condition (headlights, blower fan, rear window defogger, and air conditioner are turned off).
Ignition Timing
10±2° BTDC (RED mark (B)) at idle in P or N
- If the ignition timing differs from the specification, check the camshaft timing (see CAM CHAIN REMOVAL ). If the camshaft timing is OK, update the PCM if it does not have the latest software (see PCM UPDATE ), or substitute a known-good PCM (see SUBSTITUTING THE PCM ), then recheck. If the system works properly, and the PCM was substituted, replace the original PCM (see PCM REPLACEMENT ).
- Disconnect the HDS and the timing light.
Use the Manual With the Right Hardware
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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.
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