How to replace spark plugs **pictures**

Here is my write up with photos on a 3rd generation 4Runner spark plug install:

We are going to start with the driver's side of the 4runner:



Went ahead and picked up an OEM set of spark plugs and spark plug wires:



Notice the wires on the 4runner are numbered. The new wiring will have the same numbering system. We need to make sure that we replace each wire with its corresponding number!



Before starting job, scare off any nearby roosters. They tend to be bad omens when working on vehicles.



We need to remove some stuff out of the way so we can have room to work with:

Removing ground wire and nut



Diagnostics plug:



Once these are out of the way we should be able to have full access to the first spark plug wire, tug on it to pull out. Gently. If its stubborn, twist and pull. Work it slowly.



Careful not to drop any debris once it has been removed:



Well need a ratchet and a spark plug socket, an extension is required.





Here I pulled out the spark plug:



Compare with the new ones to make sure we bought the same ones. The used spark plugs look good. Oily, burnt or broken spark plugs are an indication of engine issues.



To install the new plugs, I recommend using anti seize lubricant. This prevents the spark plugs from sticking and allows easy removal in the future:



Apply lightly:



Install new spark plug carefully, making sure it will not cross thread. Tighten snugly.



To get to the next spark plug, we are going to have to remove some hoses temporarily or move them out of the way.






Hose bracket:



Removing these will allow access to the second spark plug:



Lightly add anti sieze and install the same manner as the first one.

Accessing the third spark plug is not so difficult, will need to just push some hoses out of the way:



I recommend installing the spark plug wiring as you install each spark plug. This prevents mix ups and makes sure that we are installing the right wire at the right plug. Remember the numbering scheme on the wiring!

Finalized drivers side:



Now the passenger side involves a little more work to access all three plugs:



Removing hose from air box assembly:



Loosen screws and clamps:





Once lose, the air box assembly can be twisted and removed:



Revealing the spark plugs..they look different!



Notice that the end of the spark plugs wires are different than the drivers side:



See the letter P? That's where they plug at!



Here, I remove the wiring, careful not to break the retaining clips!



Once the two wires up the coils are removed, the spark plugs can be replaced the same manner as the driver's side!

Remember to use anti sieze, don't over tighten, and thread carefully!

 

Very nice write-up. I have two comments.

To avoid cross-threading, I have an 18" length of 3/8" fuel tubing in my tool kit. Slip the hose over the porcelain insulator and use it to insert the plug in the threaded hole. If it's threaded correctly, plug will turn just fine. If it cross-threads, hose will slip warning you to try again. You just get a much better "feel" than using a wrench (which you still need for the final turns.)

NGK's website states that their plugs do not require anti-seize. I've been using NGK stock plugs every 30k since 1999 (170k now) with no anti-seize and no problems. According to NGK, use of anti-seize can lead to over-torquing.

http://www.ngksparkplugs.com/pdf/dyk_5points.pdf

 

Well done!
Ill chime in as well.
I like to add an extendable magnet to the tool list to pull the plug out and gently drop the new one in.
My dad gave me a tip years ago, so Ill share with everyone.
Use some electrical tape to tape your socket to your extension just incase the two come apart. If the two come apart your neighbors and family to hear every cuss word you know.

 

Thanks for the input guys! I have done the tape thing to the socket extensions. I agree with the antiseize, it's just a matter a preference. Many of us do it different ways. I always make sure to tighten them snugly because I am scared of breaking the spark plugs while I am threading them in.

 

Roosters are cocks.

 

he was cock blocking me.

 

Thank you for the tutorial. I bought my 4Runner new in 02 and it finally needs some tuning up. The plugs were a bit perplexing at first glance but this makes it a lot easier. I'm still not totally clear on replacing the wires... or the rooster. But your post will give me a great start!

 

you welcome bud!

 

About to do this later today, nice write up and pics!

 

if you change your spark plugs toyota manual is vary specific use only denso #k16r-u or ngk #bkr5eyafor the 3rz-fe engine for the 5vz-fe engine use densok16kr11 or ngkbkr5ekb-11 only should be changed every 30.000 miles the gap 3rz-fe engine 0.8 the gap on the5vz-fe engine is 1.1 dont rely that the plugs out of the box are gaped right mine were not they were way off.just passing a little knowledge

 

the information i gave you is for the 3ed gen 4runner

 

also do not cant stress this enough don't use 90 weight gear oil in your transfer case use synthetic 75-90 weight and the rear axle and front axle it is expensive $16 per pint but what is your 4runner heath worth to you.rite

 

for your drive line use synthetic grease its water resistant and you wont have to grease it so often lets face it it a pain in the ass there are 6 zerk fitting on the drive line.

 

one more thing and i will stop when you change your air filter its a good idea to change your fuel filter its important too many people forget about the fuel filter its super easy takes 10 min start the car pull the fuel pump fuse until it stalls its on the left hand side under the car you need a 10 mm socket and small extension a 14 mm wrench and a 16 mm wrench line wrenches are better but not necessary get some rags gas will pour out ware safety glasses ok i am done i wont bother you people anymore haha take care

 

Good write up, except for the anti seize, don't let the fools at auto zone fool you, that stuff should not be used for aluminum cylinder head applications. The added lubrication can cause an over torque condition and pull threads out of the cylinder head, also it is metalic and can cause misfires if too much is applied. Professionals who know better absolutely do not use anti seize on spark plugs.

 

you got that right if you use anti seize witch t don't recommend use very little so you don't over tighten the plug,.

 

Very informative. I also appreciate the part numbers for the plugs. I need to figure out what engine I have. Any suggestions on which type of oil is best?
Thanks.

 

I do the plugs myself. 150,000 miles on a 2005 SR5 4runner.
I do the coolant - total is 2.5 gallons.. a real biggie.. I drain and add 1 gallon.
After 20 years of spark plugs in and out you learn not to overtorque.
Car starts and runs like it did in 2005 when new. Never been to a shop - except for brakes - 1 time.
Original WP, radiator, alt., tires, 1 wheel bearing replaced/failed.
3 starter replacements.
I had a GMC Jimmy from new and the body rusted away everywhere in ten years and I sold it for $600.
'4runner has no rust on the body. NONE. Paint is like new. Under side has rust but it is superficial. Front thick support bar by the (underneath) radiator was the most rusted - where it flaked some - but not a real issue or problem.

 

I do my spark-plugs every 100,000 miles. And I changed out my coils at 300,000. My SUV is running as good as new!!!!!

 

Does the 3.4 run well on NGK Iridium plugs i am thinking about changing mine out soon and using them.

 

You have to use dual electrode plugs. Denso are the best keep it factory.

 

To tighten them the best trick is once down on the washer. 12:00-3:00, 12:00-3:00, 12:00-1:00....It works you will see....

 

I have this engine in my 95 T 100, now up to 530,000 miles, no end in sight. Used hard in my general hauling service and 2 hour daily commute. Still has good compression and gets 20 mpg. I use Mobil 1 synthetic.

 

One suggestion, if I may: I put a dab of silicone dielectric grease on ANY electrical plug I plug together. That includes spark plug wires, both ends. It really helps the connection make a better electrical circuit, and keeps any thing from getting in. I know, on the third gen the plug wires on the driver's side look pretty well sealed up, but it's just a good habit I have developed.

Have fun, all!
Pat☺

 

I do the the same with the dielectric grease. I just apply a small amount to the insulator on the spark plug. This prevents the rubber boot from sticking to the spark plug. I also use the linked swivel drive. It makes the removal/installation a bit easier.
https://www.amazon.com/gp/product/B07MH5ZDMD?ie=UTF8

 

Great write up and tutorial! I wish i could be replacing my plugs, but last year a rod started knocking and oil light came on. Any fix for that?

 

1) Verify oil pressure sensor. It may have gone bad, giving you a false indication. If it's good,
2) Replace oil pump.
3) Once oil light no longer goes on, align valves.

That's the order I'd go with. You DID check the proper oil level, and change the filter, yes? Did you try changing the oil? Maybe flush the oil with a commercial oil flush, or a small amount of diesel in the oil just before you drain it? Run it for 3 or 4 minutes with the flush or diesel in, then drain it. Make sure the truck is warmed up first.

Just me.
Pat☺

EDIT: Just a quick side note: The FSM calls out 13 ft/lbs of torque for the spark plugs. Without anti-seize.
Pat☺