Dual electrode plugs?

The tone of your response sounds argumentative. If that's my fault due to my previous short response, I apologize. I'm an engineer with poor social skills.

You would want a coil per plug to eliminate the waste spark, which is wasted energy. It also increases plug life, eliminates the plug wires, and allows you to optimize the timing per cylinder. Modern cars have been moving to coil-on-plug for a while now.

Dual plugs are a completely different topic.

 

Each plug does not require its own coil however if it did it would make for a more costly and complicated ignition system... Toyota likely did it this way for a middle ground for logistics and cost. I am not sure if this is emissions, cost cutting, both, or something else. I can see cost as half the coils used, much cheaper plugs used, longer plug service life, simpler ignition system, ect however emission wise I can not see this very easily being true. Could you touch on this and how you know this to be true? Not saying you are wrong just looking for some sort of evidence to back up your info.

 

How's this work? What will the tell-tale of a vacuum leak be if I do this?

 

Not sure water will work. I always take starter fluid and spray lightly around any areas a possible vac leak could be. If engine rpm or sound changes you have found the leak location. You could always take everythin apart and reassemble with new gaskets sealant vac hose ect however this may not be necessary.

 

You will have a tone change in the engine as well as a brief rpm change. Engine might smooth out or run more rough. Watch where you spray as you might see the water vanish in a certain spot compared to the surrounding area.
Your looking for a change...

 

I was under the understanding that the Dual electrode spark plugs are used due to the waste plug ignition system used in these vehicles. Every other firing is opposite in polarity and results in a higher rate of deterioration of the electrode.

Use of the Iridium plugs in a cooler SC system works because there is very little degradation of the iridium electrode compared to copper.

 

The SC system calls for a "cooler" combustion of the cylinder gases and the plugs are less prone to wear as the iridium electrode does not degrade like the (dual) copper ones.

 

That's all correct. See post #14 above.

 

Going from a distributor system to coil on plug system was very expensive when Toyota developed this engine. 3 coils was a "best of both worlds" approach. Cheaper than 6 plugs with pretty much the same result. Spark plugs wore out faster but it wasnt too hard to put another ground on the plugs. Not an uncommon setup for early to mid 90's engines.

 

If you're talking about my earlier post, I probably didn't explain the two uses of the word 'dual' well: dual-electrode and dual-platinum.

Dual-electrode means two physical ground electrodes coming up from the threaded part of the plug.

Dual-platinum is usually a single-electrode plug (but not always). It's more of a marketing term to distinguish it from the cheaper single-platinum.
- Single-platinum means it has a platinum center electrode but the ground electrode is not platinum.
- Dual-platinum means both the center electrode and the ground electrode are made of platinum.

You can also have a dual-platinum plug that is also dual-electrode. In this case, the center electrode and both ground electrodes are all made of platinum. NGK Laser Power plugs (BKR5EKPB-11) are like this.

On the NGK website:
- G-Power plugs (BKR5EGP)are single-platinum single-electrode
- Laser Power (BKR5EKPB-11) are dual-platinum dual-electrode
- OEM plugs (

$7 BKR5EKB-11 NGK Spark Plug Stock # 3967

BKR5EKB-11) are non-platinum, dual-electrode

rockauto.com also has good pictures and it breaks down the plugs by the types described above (dual-platinum, dual-electrode, etc.)

 

Im curious if they need dual electrode plugs, then why does TRD call for a

$7 Denso IK20 Iridium Power Spark Plug, (Pack of 1)

Denso IK20 that is a single electrode plug?

 

Assuming you are talking about a Super Charged system: The IK 20 is a "cooler" plug that helps to reduce incidence of pre-detonation. The fact that it is iridium reduces significantly the accelerated wear seen with copper electrode plugs and therefore does not need to be Dual Electrode.

Review some of the previous posts in this thread, there is some good info.

 

Tacoma Mike:
"If that is all you did was yank the plugs and wires you must have done something you don't realize." end.

I am thinking this as well Matt. Changing plugs and wires is a basic skill.

All the new electrodes look like they were spaced evenly and gapped proper?.

A loose plug socket can lay over during tightening and crack the insulator,,good judgement needed there during install without a cushioned socket.

Did you happen to lay on or elbow hard a bundle of wires in the engine bay while wrenching? Did one of your new plug wires get smashed? OEM wires or ??.

 

Yea I've done some research and talked to Gadget from URD and its a go with the plugs.

 

Clearly, I did something. Figuring out what - that's the trick. I'm leaving work now. This evening I'll try to find a vacuum leak as that seems most likely to me. It had the same symptoms with old wires and new wires, and two different sets of new plugs.

 

I hunted for a leak. Maybe, maybe found a small one. That particular hose was cracked where it hooked up to the black box on the side of the air intake. I don't think that was The Problem, though, as there wasn't an appreciable difference when I completely unplugged it. I changed it, anyway.

However, today it has been starting better and driving better (more on the driving in a minute*). It is idling around 740 or so, instead of 490.

I have a theory based on nothing Toyota.

In addition to changing the plugs (there's always something else, right?) I had the battery disconnected for a little over an hour. Is it possible that the ECU had to re-learn how to drive? Or, is it possible that the ECU got accustomed to the abnormally large gap in the old plugs and had to adjust for a correct gap? I don't have a good gapper, but I'd guess that the gap on the old plugs was about 1.5 times the gap on the new plugs. Maybe more.

*I'm very new to this truck. I'm coming off a 2002 F-250 (gas). I'm not sure if I feel this truck stuttering ever so slightly when accelerating, or I'm feeling "little truck, little engine, 200k miles". Probably, I should have driven it a week before I changed the plugs so I had a better baseline.

 

WTF MATT.
You never said anything about disconnecting the battery,
That kills any memory of the learned values for idle and start.
Your low idle on a reset indicates you need to clean your throttle body.
It will come back up to normal after it learns
We can only give you good info with good info given to us.
I think you wasted a lot of time chasing something that isn't there.
There is info on here for cleaning your throttle body.
I would suggest you do that next...
Once you do that your idle may be a lot higher than now.
Disconnect your battery again and start from scratch.
Put your new stuff back in and I think it will be ok.
Let us know how it goes..
Good luck

 

Sorry. The battery was in an attempt to fix a different problem (blinking air bag light) so I didn't have it tied together in my mind. Thanks for hanging in there with me.

I'll read about cleaning the throttle body, if I can find it. At least it did lead to the solution to a problem I didn't know about.

There's more coming. I bought an old truck and an old truck's problems. I'll be a while bringing it up to snuff. There'll be a question about the leaf springs later . . .

 

Final follow up post here.

Thank you, everyone, for the help and advice. Sorry the "Dual electrode" thread deviated so far from it's origin.

Tonight I replaced the PCV and cleaned the throttle body. I don't think there's an IAC on this truck,but I'm willing to be convinced otherwise. After doing these two things there was a marked change in starting and idling. I did a little seafoam-in-a-vaccum-line treatment (those guys really should put a graduation window on the side of the bottle).

I think it's running better. I *think* I'm still getting a little stutter on acceleration. It's most noticeable going uphill. I almost sort of maybe think it's lugging a little bit. Do you have to drive it a little bit mean?

Anyway, I consider this project mostly complete-ish. On to the next one.

Thanks again.