Sparkplugs?

[nsmitchell]

I'm interested to see peoples spark plug preferences. I prefer Bosch Platinum or Iridium. NGK is the OEM plugs used in the Yaris and they are great as well. I used some plugs once called E3 and they sucked in my Tacoma and my Odyssey. They actually made my Odyssey run like crap. Some plugs promise better performance. Anone know of any that do, and if so, do they?

[whoguy]

I only use Bosch. Have had cracked NGK's in the past.

[Chris07LB]

Pricey, but in all my supercharged trucks, I've run Denso Iriduim plugs. Dont know if its worth the price to try in the Yaris though..

Biggest mistake, is people fail to GAP their plugs correctly.. they dont just go from the box, into the car!

[Violin]

Do you know of a local supplier for them?

[acrbill]

My manual says the Yaris comes with Iridium plugs from the factory.
I have always been a Champion copper plug guy myself.

[Violin]

NGK also has an "Iridium" line. Does the manual specify the manufacturer? Those Densos run about $10 apiece online.

[Chris07LB]

Denso isn't for the budget buyer.. but not sure if it will make as big a deal, as on a boosted engine.

[acrbill]

I'm sure Toyota went with an iridium plug for longevity. Any plug will do the job.
I used to spike to 24psi in my turbo PT and I never had an issue with the copper Champions. I would change them out every other oil change though since they where so cheap.

[07WYarisRS]

NGK or Denso

Bosch and champion are both designed with 2 piece insulators. PISS POOR construction design and they know it so do the auto mfgs and that's why you don’t see very many auto mfg's using their products. What happens is as the plug/insulator erodes along the heavy electrode, the 2 piece insulator can separate and usually does and this allows the plug to arc out internally causing plug miss-fires. If not changed often enough the insulator become week and will eventually crack and break off and fall into the engine.

With an Iridium plug NGK or other the fine wire design along with the iridium plated electrode dissipate heat mush better and eliminate erosion and because They have a 1 piece insulator design they can't arc out/short out and that's what makes the longest lasting plug.
The only way to crack the insulator is to drop the plug or run it under extreme detonation conditions.

I have a champion plug test machine. Beside the bead blasting abilities, It has a high psi compression chamber /combustion chamber simulator that allows you to test fire plugs under compression, it also uses intense lights and magnifying scope to carefully inspect every detail of the plug. I have used this machine for years to read and inspect plugs from my race engines. I use it to dial in jetting and inspect plugs before and after use for any problems. I can say with out any doubt NGK and Denso have by far the best plug construction and quality. Both are built to the same basic specs with some small differences but some things are identical like indexing points, thread depth, body construction and insulator design etc. Firing tip design and stud mounts may be slightly different but overall they are the same plug.

[Katana]

Generally, do you think that it worths the extra cost?

[acrbill]

I would keep the stock plugs in there. People spend big bucks on iridium plugs and we have them stock.

[Violin]

I just rolled over 30,000 and was getting ready to replace the spark plugs as I always have for the last 30 years when I read the manual and saw that they don't need to be replaced for another 90,000 miles!

Do the NGK Iridium plugs really last that long?

[YamilR]

This is what I put on my Yaris

http://www.partsamerica.com/ProductDetail.aspx?MfrCode=BOS&MfrPartNumber=4501&PartType=960&PTSet=A

[YarisTom73]

NGK Laser Iridium, for sure...Champions are best for lawn mowers and 4 wheelers :laugh:
Everybody has a preference. This thread could carry on until 2012. I just avoid the American brands: Allied signal (Autolite, Champion) are about the worst IMO. Bosch is the second best for sure, they have crazy testing facilities, check out their website.

[flint_mica_manual]

I'm interested to see peoples spark plug preferences. I prefer Bosch Platinum or Iridium. NGK is the OEM plugs used in the Yaris and they are great as well. I used some plugs once called E3 and they sucked in my Tacoma and my Odyssey. They actually made my Odyssey run like crap. Some plugs promise better performance. Anone know of any that do, and if so, do they?

I have owned an 85 VW golf, a chevette, and 2 geo storms. I tried Bosch platinums in every one of them, and they all failed after 100 miles -- misfiring, bizarre idiling, etc. . . .I always then replaced them with the cheapest AC delcos or NGKs I could find -- being all ticked off at blowing all that money on the Bosch platinums, and I never had a problem. I ain't a big fan of Bosch, but NGK and AC delcos are good plugs IMHO.

[nsmitchell]

I have owned an 85 VW golf, a chevette, and 2 geo storms. I tried Bosch platinums in every one of them, and they all failed after 100 miles -- misfiring, bizarre idiling, etc. . . .I always then replaced them with the cheapest AC delcos or NGKs I could find -- being all ticked off at blowing all that money on the Bosch platinums, and I never had a problem. I ain't a big fan of Bosch, but NGK and AC delcos are good plugs IMHO.

When you say "failed", do you mean fouled or what? Ive used Bosch Platinums in many of my cars and they always made them run great. Smooth and sure firing. You were putting them in pretty old cars and I wonder if the problem wasn't the plug, but the engine. Were they gapped correctly?

[YarisTom73]

That's the biggest thing: you have to be very particular in your gapping. The only plugs I've seen that are truly "pre-gapped" are the Bosch +4's and +2's. They don't have any adjustment. I used Bosch in my 88 S10, and to this day they run perfectly. All in the details, IMO...:iono:

[pabsan]

in conclusion, what benefits would my yaris obtain from iridium plugs? is it worth the money?

[keesue]

in conclusion, what benefits would my yaris obtain from iridium plugs? is it worth the money?


The Yaris comes with Denso Iridium Plugs, yes? I'm too lazy to pull 'em....lol

[Violin]

NGK Iridium.

[keesue]

NGK Iridium.

ahhhhh....thanks, I was thinking of Denso as in the oil filter...duh...

[Toyota Technician]

ngk and denso is basiclly the same plug when u replace plugs in a 5 vz-fe 3400 tacoma angine and a 1gr-fe 4.0 tacoma engine if they have the factory plugs in it then it will have ngk plugs on one bank and denso on the outher bank.

[keesue]

I understand the life expectancy of these plugs is close to 100K, yes?

[Violin]

The manual says to replace them at 120,000 miles.