Owners of other Toyota or Lexus vehicles such as the Tundra, 4Runner, Hilux, Highlander, C-HR, Avalon, Camry, Corolla, Supra, Land Cruiser, Prius, RAV4, Mirai, Sequoia, Sienna, Yaris, CT 200h, ES 300h, RX 350, GX 460, LX 570, NX 300, RX 450h, UX 200 and UX 250h may also find these DIY instructions to be helpful.

The OEM (original equipment manufacturer) iridium tipped spark plugs in this 2020 Toyota Tacoma TRD Sport are part number Denso FK20HBR8 (3491).

A few other compatible replacement spark plugs with their part numbers are as follows: Bosch FR7NII35S, Autolite XP5363 and E3 E3.68.

The tools needed to complete this procedure include a 10mm socket with a 1/4" drive ratchet, a 12mm socket with a 3/8" drive ratchet, a 5/8" spark plug socket with a set of wobble extension bars and a tube of dielectric grease.

The first few steps are to open the hood, lift up the front edge of the plastic engine cover and then pull the "C" shaped retaining clips on the back side of the cover off their mounting bar.

The three spark plugs on the passenger side of the engine are relatively easy to access with just one silver metal bracket, which holds the wire harness in place, covering the center ignition coil.

Remove the silver bracket by turning the bolts in the counterclockwise direction.

You could also disconnect some of the electrical connectors on the passenger side of the engine for easier access.

An optional step for easier access to the spark plug closest to the front of the engine is to detach the air intake hose from the throttle body and the air filter box.

You'll have to detach the two black metal brackets that connect the black plastic intake manifold to the side of the engine.

The black metal support brackets are held in place by 12mm bolts.

It may also be necessary to detach a few of the vacuum hoses or pull them out of their plastic retaining clips to give you more room to reach the ignition coils on the driver side of the engine.

Loosen the single silver metal bolt that secures the ignition coil to the valve cover by turning it in the counterclockwise direction with the 10mm socket and a 1/4" drive ratchet.

Push down the release tab on the gray plastic electrical connector before sliding it straight off the base of the ignition coil.

Lift the ignition coil straight out of the spark plug well.

If you had an issue with a faulty or failing ignition coil, the OEM part number is Toyota 90919-A2008 (E11 10R-04 8610).

If you have an OBD2 Scanner (also known as an OBDII Scan Tool), some of the ignition coil DTC (diagnostic trouble codes) you might see include the following: P0350, P0351, P0352, P0353, P0354, P0355, P0356, P0357, P0358, P0359, P0360, P0361, P0362, P0363 and P0364.

I always use some electrical tape, Gorilla tape or even painter's tape to secure the spark plug socket to the extension bar to prevent it from popping off down at the bottom of the spark plug well.

Lower the socket down into the well and push it over the top of the old spark plug.

Carefully loosen the old plug by turning it in the counterclockwise direction.

If you have trouble loosening the old spark plug, try spraying a very small amount of penetrating oil down into the well and allow it to seep into the threads for at least 10 to 15 minutes.

Once the old spark plug is loose, detach the ratchet from the extension bar.

Spin out the old plug the rest of the way with your fingers.

Inspect the old spark plug for any soot, oil or damage.

If the old plug is dark black and covered in soot or sludge, the engine might be burning oil and should be inspected by a professional mechanic.

If the old plug is ashy white, the engine may have been subjected to overheating. It may be necessary to choose a spark plug with the appropriate heat range for your climate.

The OEM spark plugs in this 2020 Tacoma TRD Sport are the Denso FK20HBR8 iridium tipped.

If you have a spark plug gap gauge tool, check the gap on the new plugs. The OEM Denso FK20HBR8 plugs should be gapped to .032" (or 0.8mm).

Push the new spark plug into the socket.

Your socket should have a magnet or a rubber insert to securely hold the spark plug in place.

Carefully lower the spark plug into the well. Avoid hitting the electrode tip against the valve cover or the sides of the well.

Spin in the new spark plug by hand until it makes contact with the cylinder head.

Starting the spark plug by hand with just the extension bar will help prevent it from becoming cross threaded.

Try to avoid over tightening the spark plug to prevent from cracking the ceramic part of the plug or damaging the aluminum threads.

If you are installing new spark plugs, you may feel the crush washer collapse as you are tightening the plugs.

If you are just re-installing the old plugs after checking their condition, just tighten them to a tiny fraction of a turn past finger tight since the crush washers will have already been collapsed.

If you would like to use a torque wrench, the service manual specification for tightening the spark plugs is 13 lb-ft (or 18Nm).

Apply a small amount of dielectric grease to the opening in the rubber dust boot at the bottom of the ignition coil.

The dielectric grease will help ensure a reliable electrical connection by keeping out any moisture or debris.

Rotate the ignition coil back and forth a few times to help spread the dielectric grease.

Line up the bolt hole in the ignition coil with the corresponding bolt hole in the valve cover.

Spin in the bolt a few turns by hand in the clockwise direction to help prevent it from becoming cross threaded.

Try to avoid over tightening the bolt to prevent from cracking the plastic ignition coil housing.

Push the electrical connector straight on to the base of the ignition coil.

You should feel or hear the connector "click" securely into place.

Double check that the plug is securely attached.

Replace any vacuum lines, electrical connectors, metal brackets or bars and the air intake hose that you may have removed for easier access to the spark plugs.

Lower the front of the plastic cover and push on it to secure the rubber friction fasteners to the metal pegs on the top of the valve cover.

Double check your work to make sure the vacuum hoses, metal brackets or bars and the electrical connectors are all properly re-attached.

Start the engine and listen closely for any strange sounds. If you do hear a weird noise, immediately turn off the ignition and check your work again.

Be sure to write down the spark plug change in your truck's service records.

Please check out all of the 2016-2021 Toyota Tacoma DIY Repair & Maintenance Guides.