this question is for a friend and myself is also curious about. he recently bought single electrode bosch platinum plus spark plugs for his 97 3.4l 4runner as oppose to dual electrode. question is will this harm the engine in any way? he's been driving like this for a day now with no problem. also will this effect any emissions for smog? is platinum even worth it or should he stick with the regular ones?

 

The owners manuals go out of their way to specify DUAL electrodes and under the hood of my rig there is a sticker with a picture of a single electrode spark plug and a picture of a dual electrode plug and the single electrode is x'd out.

It seems like a silly chance to take when Toyota is so specific about what is required...

 

 

This topic used to come up about once a week but now it's almost daily.
https://www.yotatech.com/forums/show...1&postcount=21

 

he shoulda got ngk plugs

 

i knew i saw something under the hood about that. thanks for clearing that up WATRD.

 

Ok - thats all good for a n/a engine --- why does TRD specify a single electrode platinum plug for the sc - especially with the 7th?

 

They specify an iriduim plug which happens to be single electrode by design.
It's like comparing apples and oranges.

 

The platinum plugs are not efficient with our engine due to the "waste spark ignition system." They can end up causing misfires and rough running. Read this post to see why: https://www.yotatech.com/forums/show...95&postcount=1

The single-electrode plugs specified for a supercharged engine are NOT made with platinum, they have Iridium in them. The single-electrode plugs are "cooler" and help prevent ping in a forced induction application. I personally am running Denso Iridium IK-22's (single electrode) in my supercharged 4Runner, but any naturally aspirated engine should run fine with regular dual-elecrode Denso's or NGK's. Again, the issue is not really the number of electrodes, but the material the plug's electrodes are made out of. Bosch plugs, especially the ones that have platinum in them, are bad news for our engines.

 

Guys -lighten up about the platinum/iridium thing --- i wasn't sure whether the name "Iridium" actually meant it was solid iridium - you do know that platinum is typically alloyed with iridum to harden it - pure platinum is pretty soft - so I assumed it was a marketing buzz word play.

The point is that they specify a SINGLE electrode plug for the sc. I'll buy the single electrode plugs run cooler argument. But I saw URD has 2 (maybe 3) step cooler -- I think 3 prong -- plugs. Why wouldn't TRD specify those?

 

Run whatever plugs you like, just don't run Bosch Platinums.

I have heard for most supercharged applications the Iridium IK-22's work quite well. They work great for me.