Best spark plug (1 Viewer)
- Thread starter Ls430
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I would go OEM. Only engine issue I ever had with my 4Runner was due to aftermarket spark plugs.
If you want a recommendation between the two, my personal preference and recommendation is the NGK. The Denso will be fine, though; both are OE for 2UZ.
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Yes. Both are listed on the owners manual.
My bad.
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- #6
I should have been more clear with my post/question.
Interesting fact, on some Toyota motors, My 2007 FJ for instance, come from the factory with both. One side has Denso and the other NGK. Now I do not know about Cruisers since I picked up my 2006 LX470 used. Why did they do this?
gregnash
Anal Retentive Analyst
Whatever you do be sure that you purchase from a verified vendor. Lots and lots of Legit looking, but ultimately FAKE plugs out there especially on Ebay and Amazon.
This is 100% accurate.
2001LC is using some twin tip Densos right now. He seems to like them. For most people who just want to set it and forget it stock feels like the best option. You know what you are going to get. Scored 2007 LC W/63K No AHC Clean. Adding Lift, Sliders & skids!
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O'Reillys has a rebate on Denso 3297 (SK20R11).
SK20R11 Iridium has a life span of 120K, use that and you should be good for awhile. Get it from the local Advance Auto with coupons and stuff, ive never seen fake ones from Advance, only online.
That’s interesting. My dad said the same thing about his 2005 Tacoma years ago.
I do like TTs, for two reasons.
1) China has not been able to boot leg, the very thin .04mm tips of Denso TT. So I can spot bootlegs easily.
2) Denso claims lower power draw with TT, for same or great spark. This lowers coil temp, or is to say, coil runs cooler. High temps damage coils, so cool adds to life and they age with a more even power curve out put. It is why we do not want wide gap in plugs, beyond spec. Wide gaps draw more current to get spark. BTW TT are gap at 1.0mm vs book of 1.1mm new. It's also why as spark plugs walk out we blow coils, as they draw more and more power trying to achieve good combustion spark.
We have issue with spark plugs walking out. I've been hear and seeing "some " anecdotal evidence this is a Denso issues more so than NGK.
Ticking time bomb TICK TICK TICK: Spark plugs Alert Alert Alert!
TICK TICK TICK POP POP POP is a ticking time bomb, often mistaken as exhaust manifold crack or gasket leak leak. ALERT, ALERT, ALERT: Spark plugs are working themselves loose. "Walking Out" Then blowing out of head, taking their female threads of head with them! Very damaging! You think TICK...
forum.ih8mud.com
Genuine or Bootleg parts
I buy a lot of parts from on-line sellers these days, mostly form parts houses or Dealerships. Now and then I'll but from say ebay or Amazon. Seems I get Bootleg from China more often from ebay sellers. I've had some of those low priced Denso coils that look so good. But with close inspection...
forum.ih8mud.com
Note: never re-gap used plugs.
I do like TTs, for two reasons.
1) China has not been able to boot leg, the very thin .04mm tips of Denso TT. So I can spot bootlegs easily.
2) Denso claims lower power draw with TT, for same or great spark. This lowers coil temp, or is to say, coil runs cooler. High temps damage coils, so cool adds to life and they age with a more even power curve out put. It is why we do not want wide gap in plugs, beyond spec. Wide gaps draw more current to get spark. BTW TT are gap at 1.0mm vs book of 1.1mm new. It's also why as spark plugs walk out we blow coils, as they draw more and more power trying to achieve good combustion spark.
We have issue with spark plugs walking out. I've been hear and seeing "some " anecdotal evidence this is a Denso issues more so than NGK.
Ticking time bomb TICK TICK TICK: Spark plugs Alert Alert Alert!
TICK TICK TICK POP POP POP is a ticking time bomb, often mistaken as exhaust manifold crack or gasket leak leak. ALERT, ALERT, ALERT: Spark plugs are working themselves loose. "Walking Out" Then blowing out of head, taking their female threads of head with them! Very damaging! You think TICK....Genuine or Bootleg parts
I buy a lot of parts from on-line sellers these days, mostly form parts houses or Dealerships. Now and then I'll but from say ebay or Amazon. Seems I get Bootleg from China more often from ebay sellers. I've had some of those low priced Denso coils that look so good. But with close inspection...
Note: never re-gap used plugs.
I used those same plugs IK20TT, but i've read that they have half the life span of the SK20R11 ones. 60K life span vs 120K, some even said the IK should be changed out every 30K miles. What are your thoughts on it, not that it matters much to me since i like to replace stuff on my vehicles, but for others who do not have the time or knowledge to keep replacing it every so often.
Well when Denso came out with the TT, they did not give an expect life. I ask them the question. They did not respond to me directly. But they did subsequently state in their web page over 100K miles. Than I started using them.
I've not used the TT very long so I can't say for sure what is good change interval. But my with factory install plugs, re-torque at 60K is best, but 90K is okay. Lexus had been recommended replace at 60K miles.
Re torque is to insure they've not walked out, which if allowed to run loose for to long, can be very damage. They can blow out the heads, taking threads out of heads. Very bad!
I've gone to a higher torque of 16 to 18ft-lbf. I also feel it's best to replace plugs once removed. That is because crush washers do not work as well a second time. But the do work.
I feel, if replaced and torque to at least >16ft-lbf. We can just replace with each timing belt job at 90K miles. I've never seen them walk and blow out, earlier than ~150K miles. But miles are misleading. It has to do with heating and cooling cycles. But, I have seen factory loose at 60K miles.
Spark plugs are cheap insurance to protect the very price coils.
One more note; which is counter intuitive.
I've found when the spark plugs thread have anti seize used on them. The plugs get frozen in, and come out hard the whole way. One can of BG 44K per 1/2 to 3/4 tank of gas once or twice in a row, unfreeze them. I think what happens as they start walking out. Hot gasses escaping cook the anti seize and carbonize it. I've seen this twice now, so not a trend but interesting. Also one must reduce torque ~20% if threads lubed. Which one of these cases I reinstalled the old plugs and used anti seize and torque to only 13ft-lbf.
I've not used the TT very long so I can't say for sure what is good change interval. But my with factory install plugs, re-torque at 60K is best, but 90K is okay. Lexus had been recommended replace at 60K miles.
Re torque is to insure they've not walked out, which if allowed to run loose for to long, can be very damage. They can blow out the heads, taking threads out of heads. Very bad!
I've gone to a higher torque of 16 to 18ft-lbf. I also feel it's best to replace plugs once removed. That is because crush washers do not work as well a second time. But the do work.
I feel, if replaced and torque to at least >16ft-lbf. We can just replace with each timing belt job at 90K miles. I've never seen them walk and blow out, earlier than ~150K miles. But miles are misleading. It has to do with heating and cooling cycles. But, I have seen factory loose at 60K miles.
Spark plugs are cheap insurance to protect the very price coils.
One more note; which is counter intuitive.
I've found when the spark plugs thread have anti seize used on them. The plugs get frozen in, and come out hard the whole way. One can of BG 44K per 1/2 to 3/4 tank of gas once or twice in a row, unfreeze them. I think what happens as they start walking out. Hot gasses escaping cook the anti seize and carbonize it. I've seen this twice now, so not a trend but interesting. Also one must reduce torque ~20% if threads lubed. Which one of these cases I reinstalled the old plugs and used anti seize and torque to only 13ft-lbf.
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No, it was common practice. One bank got Denso, and the other NGK. Weird stuff. This was a standard, not random. When I worked for Toyota parts back in the late 90's, techs said the same thing. They always knew if the plugs were original because of this. Toyota did this for years, if not decades. My memory may be a bit clouded now, but I swear the techs noticed it during the massive V06 campaign with the 4Runners and Pickups. Why did Toyota do this? I do not know, but I would love to know.
That is also applicable to 1st gen Tacomas.
Here is my analysis of it. Kind of an exercise for my brain (this is what I do for work)
1. Suppliers: contracts/purchasing/redundancy/manufacturing capacity.
2. Performance: reliability/longevity/performance/mileage/serviceability.
Toyota builds and sells everything on a JIT model (just in time). They know that their demand can be massive, but also needs to be fluid. The easiest way to make sure they always have the plugs they need without having to cash flow them far in advance, is to find manufacturers with the right capacity, award both contracts and require them to work in parallel. I'm insulated from risk if one firm's production line goes down. I get to dictate the price as parallel contracts means I can shift to the other if one pushes back on something.
Another dynamic:
Toyota builds their entire production line around a couple of motors, and they stick with that motor for at least 5 years - usually more than 10 years. If you have relatively matched firms like Denso and NGK supplying (for example) ALL the plugs for the 1GR-FE motors that Toyota builds for a decade, that brand is simply going to dominate the other company.
Toyota doesn't want that. They want both firms constantly under the gun because their competitor is neck and neck with them on capacity, technology, quality, pricing, and availability. Toyota then has leverage over both Denso and NGK for at least the spark plugs.
If I'm Toyota and really want to prove a point, I could go as far as to put both brands' spark plugs in a motor design at the same time. It certainly proves their products can be used interchangeably and I don't care who sells which plug to me as long as I get it on time, the quality is great, and they don't ever think about changing their price.
Another dynamic:
They did it to see which product has the best longevity, reliability, and performance. With a few hundred thousand motors sold a year and how long Toyota plans to run it...sure, it makes sense to do this. But then they ran mixed plugs in the 1GR-FE for almost a decade. They had results back on the plug performance within 5 years. I think this was a business driven decision with performance/product quality data benefits.
Back to OP's question, I've run both in several 4.7's and both the NGK and Denso plugs are great.
