Ignition Coil And Spark Plug Diagnostics

IGNITION COILS 

The ignition coils are installed in the cylinder head covers, under the Noise, Vibration and Harshness (NVH) covers. Each ignition coil locates on a spark plug and is secured to the related cylinder head cover with a single retaining bolt. Each ignition coil incorporates a three pin electrical connector for connection to the engine harness.

1. Using the Jaguar Land Rover approved diagnostic equipment, check the powertrain control module for any ignition coil related DTC  s and repair as necessary
2. If there is a misfire and/or driveability issue and no DTC  information is available, inspect the condition of the ignition coil(s). Check for the following:
   1. Check the security of the ignition coil of the affected cylinder. Make sure the retaining bolt is present and tight. Refer to: SPECIFICATIONS  - For the correct torque
   2. Refer to the electrical circuit diagrams and check the affected cylinder ignition coil electrical connector(s) for poor connection, backed out pins, damage or corrosion. Repair as necessary
   3. Inspect the affected cylinder ignition coil for damage or cracking. Inspect for evidence of tracking. Replace the faulty ignition coil as necessary. Refer to: IGNITION COIL-ON-PLUG (G2244125) 
   4. Remove the affected cylinder ignition coil and check insulator boot for damage, cracks or evidence of tracking. Replace the faulty ignition coil as necessary. Refer to: IGNITION COIL-ON-PLUG (G2244125) 
   5. If there are no visual faults with an ignition coil from an affected cylinder, swap the ignition coil with one from a known good cylinder and retest. If the issue has changed cylinder, replace the faulty ignition coil as necessary. Refer to: IGNITION COIL-ON-PLUG (G2244125) 

   SPARK PLUGS 

3. The spark plugs are installed in the cylinder head below the ignition coils. If no issues were found with the ignition coil checks, inspect the spark plugs. Check for the following:
   1. Check the spark plug of the affected cylinder for security in the cylinder head. Refer to: SPECIFICATIONS  - For the correct torque
   2. Remove the spark plug of the affected cylinder and check the ceramic insulator for damage, cracks or evidence of tracking. Replace the faulty spark plug as necessary. Refer to: SPARK PLUGS (G2244126) 
   3. Inspect the spark plug center electrode for excessive wear. Replace the faulty spark plug as necessary. Refer to: SPARK PLUGS (G2244126) . If the center electrode is not worn, check the electrode gap and adjust as necessary before reinstalling the spark plug
   4. If there are no visual faults with the spark plug from an affected cylinder, swap the spark plug with one from a known good cylinder and retest. If the issue has changed cylinder, replace the faulty spark plug as necessary. Refer to: SPARK PLUGS (G2244126) 
   5. If there are no issues found with the ignition coils or spark plugs, REFER to: ELECTRONIC ENGINE CONTROLS - V8 S/C 5.0L PETROL (G1551174) and check other powertrain components