Toyota 4 runner spark plugs
Not a big deal. Realize that the plugs from the factory are Iridium and are good for 100K miles. Assemble the following:
6 Denso IKH20 Iridium Plugs pre-set to .044 gap ($10 each) High Temperature anti-seize (crayon type is $3 at NAPA)
3/8 inch drive ratchet
5/8 inch spark plug socket
10 mm socket
12 mm socket
torque wrench (or make real sure you don't over tighten the plugs) new air filter (optional)
Start on the passenger side. Disconnect the air induction/filter assembly by un-snapping the two spring latches on the black air intake box closest to the front of the car. Once these are un-latched, fold the air intake assembly out of the way. Now would also be a good time to replace the air filter if you have not done so lately. With the air intake assembly out of the way, you now have clear access to the top of the valve cover. Along either side on top of the valve cover you will notice three black modules each held in place with one 10mm bolt with a small wiring harness connector attached. These are the coils (one per plug), and the spark plugs are located underneath. Disconnect the wiring harness connector and remove the 10mm bolt. Pull straight up on the coil and it should disconnect from the spark plug. Look down the hole and you can see the top of the spark plug 5 inches down. Using a 5/8 inch spark plug socket with a rubber 'holder' inside the socket to hold the plug, remove each plug. I had to use a 10-inch ratchet extension to provide sufficient clearance. I know it sounds goofy using a standard size socket on a metric car, but it is what it is. I make sure I get each coil back to its original location, but it really does not matter as they are all the same. Since the heads are aluminum and the spark plugs are stainless steel or monel/nickel, you have to be careful not to ruin the threads on the heads. I ONLY remove the plugs when the engine is cold. Apply some high temperature anti-seize only to the threads on the new plugs and install to 18ft-lbs of torque. Slip the coil back in place, attach the connector, install and tighten the bolt and you are done with that plug. Repeat for each plug. Re-install the air intake assembly and snap down the two latches and you are through with that side.
The driver's side is more difficult as there are things in the way. I had to remove one bracket (held in place with 2 12mm bolts) and disconnect a rubber hose underneath that bracket (it just slipped off with little effort - no tools required) in order to provide sufficient room to remove the coils. This is not as bad as it sounds, and I had both removed in under 2 minutes. Now you have access to the coils and plugs and can repeat the process. Go slow, take your time, don't get anti-seize on the plug firing tip, use a torque wrench if you have access to one. Replace the hose and the bracket and you are done.
Total time is 1 hour if you are not mechanically inclined, 30 minutes if you are.
Apr 11, 2009 |
2004 Toyota 4Runner