bought iridium spark plugs but need help

[Shinare]

Bought some spark plugs today to change them out. But stripping the bolt on my alternator really spooked me. I cant find any DIY's on changing yaris plugs. I think I can do it but is there a specific torque for tightening them back up? They gave me anti-seize stuff for them as well, how much of that do I put? Do I smear it all over the threads or just put a dot or dab or what?

Thanks for the help.

[swidd]

When I did it, I tightened them to finger tight, then just over a quarter turn past that, to "finger snug with a little leverage".

Use enough anti-seize that it will fill the plug top to bottom when it gets compressed. Don't worry about smearing it all over, it will even itself out as you screw it in. I just laid a stripe along the full length of the thread on each plug.

[sex]

13 ft*lbs. see page EM-150

[RedRide]

^ ^
Install either way stated and you will be fine.
"Anti-seize stuff" is good........ :smile:

BTW, with either method, , be sure the threads are clean and are either lightly oiled or, with AS compound applied.

[AbsolutelyRed]

Be sure to start the threads by hand, if you use a wrench to start them your chances of cross-threading are greatly increased... they're impossible to cross-thread if you finger-tighten them before you reach for the wrench.

Also, don't over-tighten them, 13 ft. lbs. is not a lot.

[junorico24]

Iridium? I'll give this a go next. I had NGK then Bosch. Bosch is smoother and quieter.

[Shinare]

OK, I have a big ole torque wrench I should be able to set it at 13ft/lbs.

The brand name I bought is "NGK Iridium IX" and was told by the man behind the counter these are "factory" and was the same price as the Bosch so said I should get these. ($6 each)

[YarisSedan]

Not a real fan of anti seize i talked to one of the developers that works for ngk and he said that for sake of courisity he wanted to see how much torque it would take to snap a spark plug so he took a block of aluminum drilled threaded holes in it and put it in a vise then he took spark plugs with a torque wrench torqued them down till they snaped he said it needed nearly 100 ft llbs before the plug actually snapped but he did the same with anti seize on the thread and it broke at 16 or 36 i cant remember the number he said but it was significantly lower because anti seize is a friction modifier.

I think they never install it on the threads from the factory for a reason.

I would take your spark plug and insert it into your spark plug tool with a extention and then hand screw them in till they are seated. Take your ratchet and hold it by the base and tightend it as hard as you can with just one hand. You wont be able to overtorque it that way. Using a large torque wrench on its lowest setting is going to ensure its not going to be very accurate. I always like to pick the torque wrench for the job that is going to be in its middle range. If you are going to be using a torque wrench only use a 1/4 or 3/8 drive. The issue is when you add things like long extension they effect the rotational torque and you are going to end up with the plugs being undertorqued and they may slowly back out over time.

[Shinare]

I might get a smaller torque wrench then when I'm at harbor freight picking up a turbo socket to extract my stripped bolt head.

Well, goodness, now I got the parts guy and several other people on here saying to use the anti-seize and now someone saying scary things and dont use it. which is it.. lol :)

[jason214]

You may find this useful.

http://www.ngksparkplugs.com/pdf/tb-0630111antisieze.pdf

[Shinare]

You may find this useful.

http://www.ngksparkplugs.com/pdf/tb-0630111antisieze.pdf

Wow, thanks Jason, thats very helpful. :)

[Geoff Peace]

You may find this useful.

http://www.ngksparkplugs.com/pdf/tb-0630111antisieze.pdf

This is all very well in theory that the plugs have an anti seize coating. In practice this is not very effective. If we are talking about 14mm. plugs they have a 26.5mm reach, that is a lot of thread to corrode. The figure given by NGK for tightening these plugs is 15 - 20 Nm. or 11 - 15 lb.ft. A light coat of copper grease on the threads and tighten to 12 lb.ft. and when you want to remove them you will not find them seized. As Einstein said, In theory, theory and practice are the same thing, in practice they are not.
Regards Geoff Peace.

[UberSilver]

I use Anti-Sez on plugs and tighten by hand, grabbing the head on the ratchet and turning until it stops. It's most likely around 15~20 ft.

Over the last 40 years I've done over 1000 plugs, and never had one brake, strip or cross thread.

I've have fixed plenty of mucked up plug threads that others have thrashed.

I've only been using anti-sez for the last 20 years. If you ask why Toyota does not? I'd guess it would be a cost thing.

[RedRide]

FWIW........
Even though (long life) iridium plugs can last up to about 90k miles, it is still recommended that you remove them at about 50k for an inspection and to insure that they are not seized. If they were somewhat seized at 50k miles, they wold be even worse at 90k .
However, most just replace them at 50k instead of just inspecting them and putting the old ones back in .

"Power" iridium plugs should be replace at about 30k to retain the full benefit of them

[auxmike]

I just swab on a dab of motor oil on the threads. That anti seize stuff cakes up and can make things tighter coming out. I experienced this when removing my exhaust muffler bolts, this big gray wad fell out of antiseize.It was tight coming out too...

[Hershey]

Was nice when the 4 plugs were on front of the cast iron engine ( mitsu 1.4 , 1.5 , and 1.6 ) . Would change those , not with the aluminum .

[Shinare]

Thanks all, I'll just put them in without the AS and check on them in another 50k miles, heh. :-)

[esse10]

it's better if you put just a little Anti-sieze. If you put too much AS that's when you run into problems of overtightening them. you'll have a hard time removing them those plugs without the AS at 90k miles....good luck though:laugh:

[RedRide]

it's better if you put just a little Anti-sieze. If you put too much AS that's when you run into problems of overtightening them. you'll have a hard time removing them those plugs without the AS at 90k miles....good luck though:laugh:

I have to agree.

As I previously said, the threads should be either oiled or, have AS compound applied .... with dry threads, it's somewhat difficult to get an accurate torque reading at such a low torque spec.

Either way, I can not see how that would cause one to over tighten a plug unless they won multiple Darwin awards. :wink:

[DMZ]

I use Anti-Sez on plugs and tighten by hand, grabbing the head on the ratchet and turning until it stops. It's most likely around 15~20 ft.

Over the last 40 years I've done over 1000 plugs, and never had one brake, strip or cross thread.

I've have fixed plenty of mucked up plug threads that others have thrashed.

I've only been using anti-sez for the last 20 years. If you ask why Toyota does not? I'd guess it would be a cost thing.

My experience mirrors yours.

I have seen broken off plugs in both iron and aluminum blocks. I was taught in automotive repair school that any thread that was going to get hot should have anti-seize.

The old school stuff was a product with lead in it called John Crane. I remember it because we always referred to it as "John Wayne."

[Shinare]

Just finished swapping the plugs per the diy. Edd China would be proud! One question... It now idles REALLY low. In the 500 rpm range. I have to admit that I accidentally left off one of the coil pack wires and started the car. After hearing it missing I looked and plugged it back in and cleared the check engine light with my phone and torque pro. Should I be worried? It idled a lot higher than that before the new plugs. My old plus looked perfect except for a tiny little miniature mound of corrosion on each gap where the spark obviously connects.

[Shinare]

Ps I used no AS.

[junorico24]

It's normal.It depends on which plug you use. Bosch spark plug makes the engine idle lower than NGK's, it also quietens and it runs smoother. But these cars are designed to idle low anyway. Just make sure you have the coil pack in the right order and torqued to spec.

[Shinare]

The idle thing seems to have evened out. hehe seems fine now.

[bryanhoule]

Regarding the low idle, I experienced it as well, and it was also temporary. I just replaced my original spark plugs (they were Denso) with new NGR IFR5T11, at 82,000 miles. Original plugs looked pretty good as far as I could tell (not an expert). They all looked the same, which I'm sure is a good thing (don't need to be an expert to know that).

Anyways, after driving around the block a few times for the first time since installing the new plugs, i parked at home and let it idle. RPM was around 450 to 500 RPM, and causing a semi shaking/ vibration of the car, that i could physically feel. i rev'd the engine for a minute or so and it went away and hasn't come back.

My theory is that the CPU is somehow re-calibrating to the new plugs, but that's only a guess.

By the way, replacing your own spark plugs is easy! I didn't use a torque wrench (too expensive), but was cautious to not overtighten, just snug. i used a "single hand" method to be sure i wasn't overtightening. Also, I put a very small amount of anti-seize on the threads.