DIY: Spark plugs and ignition coils

[46runner]

I have 186K miles on my 4Runner (‘04 V8).

The spark plugss were last changed with the timing belt at 116K miles.

There were no issues but I decided to change the plugs after 70K miles. I ended up changing the ignition coils too.

I hope some will find this DIY helpful.

Slide1.jpeg
Slide2.jpg
Slide3.jpeg
Slide4.jpeg
Slide5.jpeg
Slide6.jpg
Slide7.jpg

to be continued...

 

[46runner]

continued...
Slide8.jpg
Slide9.jpg
Slide10.jpeg
Slide11.jpeg
Slide12.jpg
Slide13.jpeg
Slide14.jpeg
Slide15.jpeg

 

[Zippy0n]

i followed your transmission fluid guide which helped me very very much

i will follow this too!!

 

[bradynasty]

Thanks for the write up! Just finished this job on my 04. Really helpful with the air filter housing.

 

[cooper30]

Nice clear pictures. Well written.

 

[awhitney1]

Very helpful, thank you!

 

[huskylover]

at what mileage should spark plugs be changed

i just bought a low mileage 61 k 2005 4runner.
from what i can see from carfax and dealer, they have just changed the oil regularly.
Do I need to change the engine coolant, transmission fluid and spark plugs as the truck is 15 years old now.
Do I need to change all these now for preventive maintainence?

 

[triethylborane]

i just bought a low mileage 61 k 2005 4runner.
from what i can see from carfax and dealer, they have just changed the oil regularly.
Do I need to change the engine coolant, transmission fluid and spark plugs as the truck is 15 years old now.
Do I need to change all these now for preventive maintainence?

Plugs should be changed when the gap is out of spec or if the spark plug is faulty; to make these determinations requires pulling plugs and given plugs are cheap, usually makes sense to pull them with the intent to replace on a 86k mi vehicle. Get Denso.

Coolant can be tested with a cheap tester from any parts store. If its not been changed . . . it probably needs to be changed. The "Asian" red formulation from Zerex or Peak are cheap and work well.


Trans fluid is something I change at 70k miles or so and Ive not seen evidence that lifetime fluid is anything but perhaps lifetime of a lease or such. Go with the Toyota WS stuff

 

[AuSeeker]

i just bought a low mileage 61 k 2005 4runner.
from what i can see from carfax and dealer, they have just changed the oil regularly.
Do I need to change the engine coolant, transmission fluid and spark plugs as the truck is 15 years old now.
Do I need to change all these now for preventive maintainence?

Use only WS type fluid in the 2005 transmission....DO NOT USE TYPE T-IV FLUID!!

Type T-IV fluid is the old type fluid use in the non-sealed transmissions and shouldn't be used in the newer sealed 5 speeds transmissions!!!

Plugs should be changed when the gap is out of spec or if the spark plug is faulty; to make these determinations requires pulling plugs and given plugs are cheap, usually makes sense to pull them with the intent to replace on a 86k mi vehicle. Get Denso.

Coolant can be tested with a cheap tester from any parts store. If its not been changed . . . it probably needs to be changed. The "Asian" red formulation from Zerex or Peak are cheap and work well.


Trans fluid is something I change at 70k miles or so and Ive not seen evidence that lifetime fluid is anything but perhaps lifetime of a lease or such. Go with the Toyota WS stuff or anything T-IV spec.

The info you posted above that I highlighted in red is incorrect info...please no one use type T-IV fluid in the newer sealed transmissions, use only WS type fluid!!!

 

[huskylover]

Use only WS type fluid in the 2005 transmission....DO NOT USE TYPE T-IV FLUID!!

Type T-IV fluid is the old type fluid use in the non-sealed transmissions and shouldn't be used in the newer sealed 5 speeds transmissions!!!



The info you posted above that I highlighted in red is incorrect info...please no one use type T-IV fluid in the newer sealed transmissions, use only WS type fluid!!!

i only have RWD . I dont have sealed transmission issues?
please confirm. i will change the coolant and brake fluids just to be safe.

 

[huskylover]

Use only WS type fluid in the 2005 transmission....DO NOT USE TYPE T-IV FLUID!!

Type T-IV fluid is the old type fluid use in the non-sealed transmissions and shouldn't be used in the newer sealed 5 speeds transmissions!!!



The info you posted above that I highlighted in red is incorrect info...please no one use type T-IV fluid in the newer sealed transmissions, use only WS type fluid!!!

for 2005 4 runner with RWD do I need to do transmission Flush or Transmission drain and fill? thanks.

 

[AuSeeker]

i only have RWD . I dont have sealed transmission issues?
please confirm. i will change the coolant and brake fluids just to be safe.

for 2005 4 runner with RWD do I need to do transmission Flush or Transmission drain and fill? thanks.

The 2WD and 4WD transmission are mechanically the same with the exception of the 4WD transmission connects to a transfer case which connects to the 2 drive shafts and the 2WD transmission connects directly to a drive shaft.

That being said to answer your question, if the ATF has never been changed before, then yes I would recommend doing so, as far as a "flush" or a "drain and fill", I would completely replace the fluid vs. simply a drain and fill, but not do a "power" flush where the fluid is completely exchanged by external pressure, but instead a complete fluid replacement using the transmission to pump the old fluid out while adding new fluid until all the old fluid has been exchanged, there are many step by step topics on how to do this on the forum.

You may also want to change power steering fluid as well, which just an FYI uses ATF instead of actual power steering fluid, look on the cap for the correct type ATF to use.

 

[huskylover]

The 2WD and 4WD transmission are mechanically the same with the exception of the 4WD transmission connects to a transfer case which connects to the 2 drive shafts and the 2WD transmission connects directly to a drive shaft.

That being said to answer your question, if the ATF has never been changed before, then yes I would recommend doing so, as far as a "flush" or a "drain and fill", I would completely replace the fluid vs. simply a drain and fill, but not do a "power" flush where the fluid is completely exchanged by external pressure, but instead a complete fluid replacement using the transmission to pump the old fluid out while adding new fluid until all the old fluid has been exchanged, there are many step by step topics on how to do this on the forum.

You may also want to change power steering fluid as well, which just an FYI uses ATF instead of actual power steering fluid, look on the cap for the correct type ATF to use.

Thanks for the advice. I changed all the fluids including power steering, transmission, brake as well as coolant. I brought it to my old mechanic. I think he used some pump to take out old fluid and pump in new fluid.
I am just satisfied that there all new fluids in the truck now

 

[huskylover]

Plugs should be changed when the gap is out of spec or if the spark plug is faulty; to make these determinations requires pulling plugs and given plugs are cheap, usually makes sense to pull them with the intent to replace on a 86k mi vehicle. Get Denso.

Coolant can be tested with a cheap tester from any parts store. If its not been changed . . . it probably needs to be changed. The "Asian" red formulation from Zerex or Peak are cheap and work well.


Trans fluid is something I change at 70k miles or so and Ive not seen evidence that lifetime fluid is anything but perhaps lifetime of a lease or such. Go with the Toyota WS stuff

Along with all fluids, I also changed the spark plugs with original Denso.
How long the spark plugs last? So next time I need to change the spark plugs would be after another 60 K miles? Thanks in advance.

 

[AuSeeker]

Along with all fluids, I also changed the spark plugs with original Denso.
How long the spark plugs last? So next time I need to change the spark plugs would be after another 60 K miles? Thanks in advance.

The spark plug duration depends on the type of plug, copper plugs are good for 30,000 miles, iridium last much longer.

Usually the V6 engine uses copper plugs..but some owners use the iridium plugs instead, the V8 engine uses iridium, I don't think you've mentioned which engine you have, or which plugs were installed?

 

[Gigachad]

Thanks for posting! I had been looking for a guide that showed how to remove the air box. In regard to the spark plugs, I've noticed a debate between ngk and denso plugs. It seems as though people typically go for denso on most parts for the the 4th gens but spark plugs are the rare exception to go ngk on. Anyone have thoughts on this? I just bought an '04 with denso plugs that only have a few hundred miles on them. Unsure if I should keep them in or swap them for NGKs

 

[AuSeeker]

Thanks for posting! I had been looking for a guide that showed how to remove the air box. In regard to the spark plugs, I've noticed a debate between ngk and denso plugs. It seems as though people typically go for denso on most parts for the the 4th gens but spark plugs are the rare exception to go ngk on. Anyone have thoughts on this? I just bought an '04 with denso plugs that only have a few hundred miles on them. Unsure if I should keep them in or swap them for NGKs

If they're genuine Denso, keep them, they're good plugs, it's what I run in my V8 T4R.

 

[mates64]

Tank you very well done