2008 Acura TL BaseFACTORY OEM SERVICE PROCEDURE

Ignition Timing Inspection

  1. Connect the Honda Diagnostic System (HDS) to the data link connector (DLC) (see step 2 in GENERAL TROUBLESHOOTING INFORMATION ).
  2. Turn the ignition switch ON (II).
  3. Make sure the HDS communicates with the vehicle and the engine control module (ECM)/powertrain control module (PCM). If it doesn't communicate, troubleshoot the DLC circuit (see DLC CIRCUIT TROUBLESHOOTING (PART 2) ).
  4. Check for DTCs (see GENERAL TROUBLESHOOTING INFORMATION ). If a DTC is present, diagnose and repair the cause before inspecting the ignition timing.
  5. Start the engine. Hold the engine speed at 3,000 rpm with no load (in the N or P position (A/T) or neutral (M/T)) until the radiator fan comes on, then let it idle.
  6. Check the idle speed (see IDLE SPEED INSPECTION ).
  7. Jump the SCS line with the HDS.
  8. Remove the right side engine compartment cover (see step 1 in DRIVE BELT INSPECTION ).
  9. Connect the timing light to the No. 1 ignition coil harness.
    Fig 1: Connecting Timing Light To No. 1 Ignition Coil Harness
    G05457436Courtesy of AMERICAN HONDA MOTOR CO., INC.
  10. Aim the light toward the pointer (A) on the timing belt cover. Check the ignition timing under a no load condition, (headlights, blower fan, rear window defogger, and air conditioner are turned off).

    Ignition Timing 

    M/T: 10° 2° BTDC (RED mark (B)) at idle in 

    Neutral position 

    A/T: 10° 2° BTDC (RED mark (B)) at idle in 

    N or P position 

    Fig 2: Aiming Light Pointer On Timing Belt Cover
    G05457437Courtesy of AMERICAN HONDA MOTOR CO., INC.
  11. If the ignition timing differs from the specification, check the cam timing. If the cam timing is OK, update the ECM/PCM if it does not have the latest software (see UPDATING THE ECM/PCM ), or substitute a known-good ECM/PCM (see SUBSTITUTING THE ECM/PCM ), then recheck. If the system works properly, and the ECM/PCM was substituted, replace the original ECM/PCM (see ECM/PCM REPLACEMENT ).
  12. Disconnect the HDS and the timing light.
  13. Reinstall the right side engine compartment cover (see step 1 in DRIVE BELT INSPECTION ).
Factory Service Tools

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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.