Replace all four ignition coils on the 2018-2024 Toyota Camry 2.5L I4 engine to restore proper spark delivery and engine performance.

Warnings

Tools required

Parts

• Ignition coil × 4 — 90919-02260 or equivalent
• Spark plug × 4 — 90919-01253 (Denso) or equivalent

Preparation

1. Park vehicle on level surface and ensure engine is completely cool
2. Disconnect negative battery terminal and wait 3 minutes
3. Remove engine cover by pulling upward on the four corner clips
4. Clean debris from around ignition coil area using compressed air or soft brush to prevent contamination

Procedure

1. 1

   Disconnect ignition coil electrical connectors
   Press down on the locking tab of each ignition coil connector and pull straight up to disconnect. There are four coil connectors visible on top of the valve cover. Note the cylinder position of each connector (cylinders numbered 1-4 from timing belt side to transmission side).
2. 2

   Remove ignition coil bolts
   Using a 10mm socket with extension, remove the single bolt securing each ignition coil. Each coil has one bolt at the top. Keep bolts organized by cylinder position if they show any wear variance.
3. 3

   Extract ignition coils
   Grasp each ignition coil firmly and pull straight up with a twisting motion to break the seal. The coil extends deep into the spark plug well. If resistance is encountered, do not force—twist gently while pulling to avoid damaging the coil boot seal.
4. 4

   Inspect spark plug wells
   Examine each spark plug well for oil, coolant, or debris accumulation. If oil is present, valve cover gasket replacement may be needed. Clean wells thoroughly with compressed air before proceeding. Any liquid contamination must be completely removed.
   ⚠Do not allow debris to fall into spark plug wells as it can damage the combustion chamber
5. 5

   Remove spark plugs
   Using a 16mm spark plug socket with extension, carefully unscrew each spark plug. Turn counterclockwise and maintain straight alignment to prevent cross-threading. Inspect removed plugs for wear, fouling, or unusual deposits which may indicate engine issues.
6. 6

   Prepare new spark plugs
   Verify gap on new spark plugs is set to 0.043 inches (1.1mm) per Toyota specification. Apply a thin coat of anti-seize compound to the threads of each new spark plug, being careful not to get any on the electrode or insulator.
   ⚠Excessive anti-seize can cause spark plug fouling—apply only a thin coat to threads
7. 7

   Install new spark plugs
   Start each spark plug by hand, turning clockwise to ensure proper thread engagement. Once hand-tight, use torque wrench with spark plug socket to tighten to specification. Work carefully to avoid cross-threading the aluminum cylinder head.
   ⚠️Cross-threading spark plugs in aluminum head will cause expensive cylinder head damage—ensure plug threads freely before applying torque
   Torque spec

   Spark Plugs - Aluminum Head20 Nm (15 lb-ft)
8. 8

   Prepare new ignition coils
   Apply a thin layer of dielectric grease to the inside of each new ignition coil boot (the rubber portion that seals around the spark plug). This prevents moisture intrusion and makes future removal easier. Do not apply grease to electrical terminals.
9. 9

   Install new ignition coils
   Insert each new ignition coil straight down into its spark plug well, ensuring it fully seats onto the spark plug. Press down firmly until the coil bottoms out. The mounting hole should align with the valve cover threaded hole.
10. 10

    Install ignition coil bolts
    Thread each ignition coil bolt by hand first to ensure proper alignment. Once hand-tight, use torque wrench to tighten to specification. Do not overtighten as this can crack the coil housing.
    Torque spec

    Ignition Coil Bolts8 Nm (6 lb-ft)
11. 11

    Reconnect electrical connectors
    Push each ignition coil electrical connector firmly onto its corresponding coil until the locking tab clicks into place. Verify secure connection by gently pulling on each connector. Ensure connectors are on the correct cylinders per your initial documentation.
12. 12

    Reinstall engine cover and battery
    Position engine cover over the four mounting posts and press down firmly until all clips engage. Reconnect negative battery terminal and tighten securely.

Reassembly

1. Verify all four ignition coil electrical connectors are fully seated and locked
2. Confirm engine cover clips are fully engaged on all four corners
3. Ensure no tools or parts remain in engine compartment

Verification

• Start engine and verify it runs smoothly without misfires or rough idle
• Check that check engine light does not illuminate after 30 seconds of running
• Rev engine gently to 2000-3000 RPM and confirm smooth acceleration without hesitation
• Scan for diagnostic trouble codes with OBD-II scanner to confirm no misfire codes are present
• Perform test drive to verify normal power delivery and acceleration under load

More procedures for this vehicle