How to Replace Spark Plugs 02-06 Nissan Altima 2.5L

Difficulty: Intermediate · About 35 min · Nissan Altima

Replace the spark plugs and ignition coils on a 2002-2006 Nissan Altima with the 2.5L engine.

Steps

1. Remove the engine cover

   Use a 5mm hex wrench to remove its four Allen bolts, then lift the cover off.

2. Remove the ignition coils

   Push in the connector's clip and disconnect it, remove the coil's 10mm retaining bolt, then lift the coil out; the same procedure applies to the other three.

3. Remove the spark plugs

   Loosen each one with a 5/8-inch spark plug socket and extension, pulling it straight out of its access hole.

4. Install the new spark plugs

   Insert each plug into the socket, thread it in by hand to avoid cross-threading, then torque it to about 15-21 ft-lb once all four are started.

5. Install the ignition coils

   Slide each coil down over its spark plug, tighten the 10mm retaining bolt by feel (stopping as soon as it's snug so you don't pull the insert out of the plastic cover), then reconnect the connector.

6. Reinstall the engine cover

   Set the cover back over the engine, then tighten its four 5mm Allen bolts.

Check your vehicle’s repair manual for exact specifications and fit.