🛠️ How to Replace Spark Plugs on a 2018 Toyota Camry

Worn spark plugs cause misfires, rough idle, hard starts, and worse fuel economy. On the 2018 Toyota Camry, factory iridium plugs are rated for 120,000 miles. Here's how the job is done, and what it costs at a dealer versus Supercanic.

Cost: Dealer vs. Supercanic

Estimated 2026 Southern California averages. Dealership prices vary by location, brand, and ZIP code. Quotes shown are for budgeting only, not a binding estimate. Supercanic has a $150 minimum charge, so a small item on its own shows as $150. Those cost less booked alongside another service, and a dealer price assumes you have already got the car there.

Tools You'll Need

Step-by-Step

1. Let the engine cool completely. Working on a hot aluminum head risks stripped threads.
2. Remove the engine cover and any intake tubing blocking access to the ignition coils.
3. Disconnect the electrical connector on each ignition coil, then remove the coil hold-down bolt and pull the coil straight up.
4. Use the spark plug socket and extension to remove the old plug. Turn counter-clockwise.
5. Compare the old plug to the gap spec (0.043 in (1.1 mm)). Gap-check each new plug before installing.
6. Apply a tiny amount of anti-seize to the threads and dielectric grease inside the coil boot.
7. Hand-thread each new plug to avoid cross-threading, then torque to 18 ft-lb.
8. Reinstall coils, hold-down bolts, and connectors. Reassemble intake and cover.
9. Start the engine and confirm smooth idle with no misfire codes.