Hi everyone!

(I suspect file size but, could not upload pic so am providing photobucket link instead) I wanted to show what the Denso Iridium IK16 spark plugs look like after 40K miles. I installed these plugs when I bought my '97 4Rnr SR5...yes, I know better now and this time I made sure to go with NGK dual electrode ones. And yes, next time I will replace at 30K. Must say though, I was surprised at how bad these IK16's look. Check-out the center electrodes! 3 plugs far-left came from passenger's side (coil pack side)...the 3 plugs far-right came from driver's side. I'm not yet sure the coorelation and reasoning for the center electrodes being in such bad shape and from side-to-side differences...thoughts??

http://s1195.photobucket.com/albums/...urrent=032.jpg

 

Pull the image code from photobucket and paste it here. The 3.4 uses a unique ignition system that sends a negative spark to one side and positive spark to the other. There really is no need to run irridiums unless you are sc'd. Then you run the ik22's. Otherwise dual ground denso or NFL are the way to go. There is actually a thread on here discussing this very issue.

 

Yes, I am a bit more educated now (thanks to the forums) than I was when I bought the 4Runr 40K miles ago. Maybe this is what the plugs normally look like but, just thought it was surprising to me and maybe others would like to see them firsthand...kinda reinforcing the other spark plug threads on iridium vs. dual ground...

 

For under $30 and 15 minutes of your time, replace every 30k.

Proactive regular maintenance is key.

:wabbit2:

 

I take it the three plugs on the right are from the passenger side?

I ran the NGK version of this plug from 2007-08 and my plugs, with 20k on them, were pretty bad. I threw them out reluctantly, and got some duals all around, and have been good to go since then.

 

Actually just the opposite...from the driver's side.

 

Agreed, and going forward will do so! With proactive regular maintenance in mind, should I also be changing, not necessarily the wires but, the coil boots on the passenger-side as well? Hadn't found info on that and this is my first distributor-less vehicle. Thanks!

 

Yep, that be normal wear on the plugs, our ignitions systems are VERY strong. Also like noted above due to the way the coils work the per bay wear is normal as well.

This is why there is a sticker saying only use dual electrode plugs, they last 2x as long.

I wounder what my plugs look like come to think of it, i had to use some BKR6E's due to being in a pinch around 3k miles ago, just normal copper plugs. Be interesting to see what they look like.

 

It looks like I need to bone up on my mechanical acumen then.

I would say the biggest difference I felt with a plug change to all duals is a much smoother idle.

 

The dual electrodes don't do anything since the spark still only jumps to 1 electrode at a time. But since you have 2 of them the spark plug lasts 2x as long.

There is also a theory that the placement of the spark due to the dual electrodes does help with idle/power a little over a normal single electrode.