How to Replace Spark Plug 02-06 Nissan Altima
Difficulty: Intermediate · About 45 min · Nissan Altima
Replace the spark plugs on a 2002–2006 Nissan Altima with the 2.5L engine, using the specified plug type and gap for the vehicle.
Tools you will need
- 5 mm hex driver
- 10 mm socket and ratchet
- 5/8-inch spark-plug socket and extension
- Magnet or plug retrieval tool
Parts and supplies
- Correct spark plugs for the engine
Steps
Remove the engine cover
Switch off the ignition and let the engine cool completely. Remove the engine-cover fasteners and lift the cover clear to access the ignition coils.
Remove the ignition coils
Unplug each coil connector by releasing its lock, remove the retaining bolt, and lift the coil from the plug well. Keep the coils arranged by cylinder.
Remove the old spark plugs
Use a spark-plug socket to loosen and lift out each plug. Inspect the wells and threads, and do not allow dirt or loose debris to fall into the cylinders.
Install the correct replacements
Verify plug type and gap against the vehicle service information; do not change a preset gap unless the manufacturer requires it. Thread each plug by hand and tighten to the vehicle specification.
Reassemble and test
Reinstall each coil and its fastener, reconnect the plugs, and refit the engine cover. Start the engine and check for smooth running or a misfire warning.
Check your vehicle’s repair manual for exact specifications and fit.