← Skyline
Autopapyrus · Nissan Skyline 2.5 V6 VQ25HR (2008)
https://autopapyrus.com/guides/nissan/skyline/ignition-coil-replacement/
Compiled automatically from service literature and owner experience. Specs are for the typical configuration — check them against your exact car before you start.

Nissan Skyline 2.5 V6 VQ25HR (2008): Ignition Coil Replacement

The VQ25HR uses coil-on-plug ignition, with one coil per cylinder. The coils sit under the decorative engine cover on both cylinder heads. Typical symptoms of a failing coil are misfires, a flashing Check Engine light, and codes P0300 and P0301-P0306. Replace the coil on the problem cylinder. If the mileage is high, it is better to replace all six and check the spark plugs at the same time.

Difficulty: Easy Time: 40-60 minutes Steps: 11 Tools: Socket with extension and ratchet (for the coil mounting bolt, usually 10 mm), screwdriver, spare plastic clips for the engine cover, compressed air or a vacuum cleaner, low-range torque wrench, dielectric grease (a small amount), spark plug socket if you are also replacing the spark plugs

Part

  • 🔩 Ignition coil (individual, one per cylinder, 6 pcs.), genuine Nissan or aftermarket NGK, Hitachi, Denso. Match the part number to your old coil: the VQ25HR and VQ35HR coils look similar but are not always interchangeable

Step by step

11 steps
  1. Shut off the engine and let it cool down. For safety, disconnect the negative battery terminal.
  2. Remove the decorative plastic engine cover. It is held by bolts or nuts and clips. If the cover has stops, carefully bend them aside.
  3. Identify the problem cylinder from the trouble code. To confirm, you can swap two coils: if the fault moves to the other cylinder, the coil is bad.
  4. Disconnect the connector of the relevant coil. Press the locking tab and pull the connector, without yanking on the wires. Do not put up with a broken locking tab: replace the connector or the coil.
  5. Remove the coil mounting bolt (usually a single 10 mm bolt) and pull out the coil, rocking it slightly along its axis. The rear coils on the left and right banks are hidden under the intake manifold and pipes. You may need to move wiring harnesses aside or remove air ducts to reach them.
  6. Before pulling out the coil, blow out the spark plug well with compressed air so debris does not fall into the cylinder. Inspect the well: oil in it points to a leaking valve cover gasket or spark plug well seal.
  7. Inspect the coil's rubber boot and the spring contact. Cracks, dark discoloration, or signs of arcing indicate a fault. Check the spark plugs: carbon buildup, an excessive gap, or melted electrodes mean they are due for replacement.
  8. Apply a thin layer of dielectric grease to the rubber boot of the new coil. Press the coil firmly onto the spark plug until it is fully seated. It should sit without any tilt.
  9. Tighten the mounting bolt. The torque is low, about 8-10 N·m (6-7 lb-ft) (check the exact value in the manufacturer's service manual). Do not overtighten, because the threads in the aluminum cylinder head are soft.
  10. Plug in the connector until it clicks. Reinstall all the harnesses, air ducts, and the decorative cover you removed.
  11. Reconnect the battery, start the engine, and let it idle. The engine should run smoothly. Clear the codes with a scan tool and take a test drive, including revving the engine. If the code returns, check the spark plugs, wiring, and connector.

Common mistakes and warnings

  • Work on a cold engine: the cylinder heads and manifold get very hot. Do not disconnect the coils while the engine is running, because they carry high voltage. Do not let dirt, oil, or water get into the spark plug wells. Do not use cheap no-name coils: they often fail after a few thousand km. If you are not confident in your abilities, take the car to a repair shop.