Owners of other Toyota, Lexus or Scion vehicles such as the Yaris, Matrix, Prius, Camry, Corolla, Sienna, RAV4, Tundra, FJ Cruiser, Venza, Highlander, Avalon, Sequoia, Hilux, Land Cruiser, IS 250, ES 350, GS 350, tC, xB, xD, iQ and FR-S may also find these DIY instructions to be helpful.

The tools and other items required to complete this procedure include the following: a 10mm socket, a 12mm socket with a 1/4" drive ratcheting wrench, a standard Phillips head screwdriver, a 5/8" spark plug socket, an extension bar, a 3/8" drive ratcheting wrench and a tube of dielectric grease.

A few compatible replacement spark plugs with their part numbers are as follows: Denso (3381) K20HR-U11, NGK 6619 LFR6AIX-11, Autolite APP5325, NGK (4904) ILFR6T11, Denso IKH20TT, NGK (7787) LFR6C-11 & Bosch (9613) FR7NII33X.

Loosen the two nuts that hold the engine cover in place by turning them counterclockwise with the 10mm socket and 1/4" drive ratcheting wrench.

Set the two nuts aside in a safe place.

Lift the front edge of the engine cover and then slide it forward to disengage the "C" sockets on the rear edge from the mounting bar.

Set the engine cover aside in a safe place.

If you have access to compressed air or a wet/dry shop vacuum, clean off the top of the engine to help prevent from having debris fall down in to the cylinder well when you are replacing the spark plugs.

Loosen the hose clamp by turning it counterclockwise with a Phillips head screwdriver.

Flip open the two metal latches on the front edge of the air box cover.

Set the air box aside in a safe place.

I'd recommend only checking or changing one spark plug at a time to further prevent from having debris fall down in to the engine bay.

Press in the tab on the ignition coil module before sliding the power plug straight out of its socket.

Set the 10mm bolt aside in a safe place.

Gently lift out the ignition coil and set it aside in a safe place.

Gently loosen the old spark plug by rotating it counterclockwise.

Try to avoid using excessive force to loosen the old spark plug to prevent from cracking the ceramic portion of the plug.

If you have trouble loosening the old spark plug, spray a small amount of penetrating oil such as PB Blaster, Liquid Wrench or Kano Kroil and wait at least 15 to 30 minutes before attempting to loosen it again. If you don't have any penetrating oil, try spraying some WD-40 or warm up the engine for a few minutes to help expand the metal engine block.

The OEM spark plugs on the passenger side of the engine are Denso (3381) K20HR-U11.

The three OEM spark plugs on the driver side of the engine are NGK part number (7787) LFR6C-11.

If you have a spark plug gap gauge, make sure that the new spark plugs are the correct .044 gap or what the manufacturer specifies on the box.

(An optional step is to apply some anti-seize lubricant to the threads on the new spark plugs. Most spark plug manufacturers recommend that you should not use anti-seize since it can lead to over tightening. But it might also make it easier to remove the old iridium spark plugs after another 100,000 miles has passed.)

Push the new spark plug in to the socket and lower it down in to the cylinder well.

Your spark plug socket should have a rubber insert or a strong magnet to keep the new plug in place.

Starting the spark plug by hand will help prevent it from becoming cross threaded.

If you are installing a brand new spark plug, tighten it to just past the point when you feel the new crush washer collapse.

Do not over tighten the spark plug to prevent from cracking the ceramic body or stripping the aluminum threads.

Double check that the new spark plug is tight before moving on to the next step.

The dielectric grease will keep out any moisture and help to prevent corrosion.

Spin in the 10mm ignition coil bolt a few turns by hand in the clockwise direction to prevent it from becoming cross threaded.

Tighten the bolt with the 10mm socket and 1/4" drive ratcheting wrench in the clockwise direction until it is snug.

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

To replace the spark plugs on the driver side of the engine bay, it would be best to remove the two metal bars and disconnect some of the rubber hoses.

Both of the metal brackets are held in place by two 12mm bolts.

Tighten the hose clamp by turning the Phillips head screw in the clockwise direction.

Line up the two "C" shaped sockets on the rear edge of the plastic engine cover with the mounting bar and push them back together.

Spin on the two 10mm nuts and tighten them in the clockwise direction.

Start the engine and listen for any strange sounds that might indicate a loose spark plug or a disconnected power plug.

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

For more, check out my other 2005-2015 Toyota Tacoma DIY Repair & Maintenance Guides.