Any specific instructions for changing spark plugs? looks pretty tight...maybe I shud just pay a toyota mechanic ($120. per hour in my City)??!!

 

If you are going to get into wrenching on your own truck like most of us here, plugs are about the best place to start learning. They are easy to do and paying someone $120 to do plugs would be like paying $120 for a meal IMO. Maybe some people would, not me.

It's a little tight in there, but I've never had any problems getting to them. Just move what you need to out of the way. I suggest getting an inch lb. torque wrench - it'll come in handy in the future for a lot of things. The torque for the plugs is 167 in. lbs.

Remove 1 wire and 1 plug at a time, then replace them. Don't remove all the plugs and wires at once because it can get confusing trying to remember the order if you're not familiar w/ the engine. Put a little dab of anti-seize compound on the threads of each plug before installing and put a little dielectric grease where the wire boots contact each plug. And the most important thing:

Use NGK #BKR5EKB-11 or Denso #K16TR11 plugs only. Don't let the auto parts store sell you Bosch plugs.

For wires, use: Denso #671-6182 or NGK #TE66. You'll only get 3 wires because the coil packs sit directly on top of the other 3 plugs.

 

Thanks...appreciated...I'll pick up the plugs you suggest tomorrow and put them in. I do usually just take it to the Toyota service dept but with this kind of mileage it doesn't seem worthwhile spending that kind of money any more.

 

Warning: The hardest plug is the driver's side rear. Take your time; don't force it. Definitely the easiest one to strip. Good luck!

 

another tip: when your putting on the new plugs, use a piece of fuel line (or similar sized hose) and attach to the boot end while holding the other end to get the plug started on the threads.

If u just crank down with the ratchet right off the bat and the threads arent aligned u chance ruining the plugs. just be delicate

 

find a good writeup and print it out so you can arrange all the supplies and tools needed.

I think you can find one at 4x4wire or heck there is likely one even on Yota Tech or t4r.

Follow their advice about cleaning your work surface areas before you remove any spark plug boot. This way you have no worries of any foreign substance entering while the plug is out.

Have another vehicle available if possible for that emergency run to the parts store.

I am a total mechanical idiot and with my teenage son assisting we were able to accomplish this. A large part of the job is removing the air intake assembly to free up the space on the passenger side to do the work. Once you do that side you will gain the confidence to attempt the drivers side. I personally would not attempt the drivers side first but that is just me.

Consider splitting the job into 2 halves if that makes it more manageable for you. A few specialty items make the job even easier. I bought one of those cheap plastic plug wire boot pullers and it helped this old guy to get better grip on the boots without pulling on the actual wires.

And as stated above get heater hose or clear vinyl tubing to fit the spark plug heads.Take your new spark plug to the store to be sure to get the right size. This extends your reach down into the dark recess of the ports-you can start the plugs by hand using this tubing and get a better feel for dead on threading and avoiding cross threading.

Post your city of origin and 3rd gen vehicle specifics-could be one of us just down the road who would gladly help you out with this. This is a good first wrench step to enable you to tackle a variety of upgrades along the way. Do not be intimidated- this is how we all got started with our 3rd gens.

And welcome to this fine forum. Glad to have you aboard.

 

i use an extension with no ratchet attached to start the plug. lot easier than trying to reach in. i have yet to crossthread anything. good luck.

 

About to tackle this myself. First time into my 4Runner engine bay, but have been inside my other vehicles quite a bit. I was confused by the 3 dual-plug coil packs on pass side and none on the driver's side, that threw me for a few minutes. Also think it's a little screwy that they stuffed the coil packs under the intake plumbing just to make it more interesting, I guess.

I'm having misfires and engine shudders when trying to accelerate around 55mph so hope new plugs take care of the problem. Not 100% sure on the history of this truck so would not be surprised if they are original @ 148K.

And as far as finding a good write-up? Haven't found one yet.... I'll probably take pics and add to this thread just for fun.

 

Ok, here goes...... I bought six NGK BKR5EKB-11 plugs from Advance Auto for just under $26. I already had the tools I needed:

- 5/8" Plug socket
- Ratchet and extensions (8" and 3")
- 10mm box end wrench (mine are ratcheting, very helpful)
- 10mm socket
- 8" parts grabber
- Dielectric grease
- Wire gauge
- Phillips and flat screwdrivers
- Nitrile gloves

NGK: BKR5EKB-11
Gap: 1.1 mm (0.043 in.)
Torque: 18 Nm (13 ft lb)

View of the plug locations on driver's side:


View of the passenger side, coil packs are obscured by intake. I've marked the various things that need to be detatched, unplugged, or loosened on the intake to remove the section between the filter box and the throttle body:


1. Remove the wiring harness from the left side of the intake (2 places):



2. Remove 3 vacuum tubes from the box, loosen the upper and lower clamps.
3. Remove the lower end of the intake first, drop it down into the engine bay, pull upper end off throttle body, then remove the intake from the engine bay.

Now you can clearly see the 3 coil packs and the plug wires leading to the driver side:


4. Remove the 3 plug wires from the coil packs. Due to the custom stock lengths, there's not much chance of mixing them up so I removed all 3. If your plug wires are not different lengths, then removing them one at a time is advised. Release catch by sliding the tip of a flat screwdriver under the latch and pull up on the plug wire boot.


5. Unplug the signal wire from each of the coil packs and remove the 10mm bolt holding it to the valve cover.
Changing the plugs on the passenger side is pretty easy, actually.


6. Remove the coil packs by pulling gently off the top of the plugs:


7. I used 2 extensions on my 5/8" plug socket to get to the plugs:


Pic of the 3 passenger side (NGK) plugs:


Pic of the new NGK plugs:


Close-up of the new NGK tip:


At this point, you can check the gap of both sides with the wire gauge, and apply anti-seize to the threads.

8. I used a parts grabber on the end of the plug to re-install the plugs. This gave me the "feel" I wanted to make sure the plugs were not cross-threaded. I did not have anti-seize to put on the plug threads but it is recommended.


Before I put the passenger side back together, I took a good look at things under the intake that I normally can't see.
This is one of those things I probably need to replace:


9. When putting the coil packs back on, apply some dielectric grease to the signal wire contacts and the driver side plug wire contacts to keep the contacts from corroding. Obviously if the contacts are corroded when you remove them, they need to be cleaned up with contact cleaner.

10. Moving to the driver side, it's necessary to move some things out of the way starting with the ground wire next to the diagnostic plug (10mm bolt):


11. I also moved the throttle cable bracket back towards the passenger side (10mm bolt):


Driver side Denso plugs:


Took about 90 minutes, including taking pics and cleaning a few things as I went. Pretty simple one-banana job.

 

thats a good write up how ever you will need anti seize on the threads of the plugs or your gonna hate your self when its time for new ones also i recommend putting tape around socket to the extension that way it dont fall off

 

Elton, you've scared me enough I'm going back in on Monday and put anti-seize on the threads....

Too bad I didn't do that on the 300ZX when I changed her plugs, but I'm not going back in there any time soon. Much more difficult job.

 

Elton has a good point about the anti-seize and I do agree it's important, but seeing as though you managed to get those old rusty plugs out (I'm guessing those are the factory plugs!), the new ones aren't going to get that crusty for a while. If it were me, I would just let em be.

 

Did I miss the gap check? Be sure to use a wire style-type gapper. And for the record I have, on numerous occasions, had to adjust the "already gapped by the factory" plugs because they were so far out.

 

Ripainter,
You have to split the gap in 1/2 - .22 from each electrode to the center right? That's what I've read.

 

I have always followed what the FSM states, and gapped each electrode of the dual-electrode plugs accordingly with no issues. If you know of something that states otherwise, please let me know ASAP. Thanks!

 

I've come across a few threads like this one:
https://www.yotatech.com/forums/f2/s...estion-186032/

 

last 2 sets ive done right out of the box with out problems as i dont got a fancy feeler gauge to check them

 

I didn't attempt to gap due to the curvature of the ground tip. Didn't want to mess it up.

 

That's what I'm saying though. If you use a wire-type gapper, you can check the gap with no damage. Last few sets have been way off from the factory. And I mean off one from the other, not just both being out the same.

It's a critical step that you might want to add to your good write-up.

 

The thread quoted above basically says you don't need to gap. Personally, I visually check each plug to make sure it hasn't been damaged, and as long as there is consistency with all plugs (and the dual tips), I don't see the need to mess with it. The dual tip (as it appears to me) in part is to keep a more consistent spark over the life of the plug (better reason below). If one side sparks more than the other, the gap will increase and the spark will "jump" to the other side. So basically, the gap you start with is not overly critical due to the redundant paths, and the self-balancing mechanism of the spark jumping the smaller of the two gaps. It would be really interesting to see this plug "in action" with a high-speed camera.

Related sidebar: The "waste spark" ignition system in the 5VZ-FE appears to fire the plug twice as often as in "normal" 4-stroke engines. It fires on both compression (normal) and exhaust (i.e., a wasted spark) stroke, so the plugs will deteriorate twice as fast which is why these engines call for a dual-ground plug. Otherwise you'd be changing the plugs twice as often.

I love learning new things....