Help with Denso Problems - burnt them??

[darebren]

I am replacing my Denso IT-20 plugs with another kind... and when I took them out here is what I found..please let me know if it sounds like I am running too lean or rich and what other problems there might be...

I had 15,000 miles on them...and the last 100 miles I used a wet shot of nitrous at 75hp and only tried it for less than half a 10lb bottle...

I removed my Denso plugs and they were all in the exact same condition, absolutely no difference between cylinders...but here is what they looked like if I can describe them

at the base of the ceramic where it meets the metal (about the middle of the whole plug)..around the ceramic it is yellow/brown discolored.

the threads are light brown and the bottom of the threads the part in the cylinder has black soot on it.

the back of the metal elctrode (the little bent part that creates the gap) is almost white

the center of the elctrode (the little part that makes the spark) is the size of a pin..I thought it was thicker when i put them in, but all that is left is the same size as the sharp point of a needle sticking out of the ceramic.

[jspradii]

I am replacing my Denso IT-20 plugs with another kind... and when I took them out here is what I found..please let me know if it sounds like I am running too lean or rich and what other problems there might be...

I had 15,000 miles on them...and the last 100 miles I used a wet shot of nitrous at 75hp and only tried it for less than half a 10lb bottle...

I removed my Denso plugs and they were all in the exact same condition, absolutely no difference between cylinders...but here is what they looked like if I can describe them

at the base of the ceramic where it meets the metal (about the middle of the whole plug)..around the ceramic it is yellow/brown discolored.

the threads are light brown and the bottom of the threads the part in the cylinder has black soot on it.

the back of the metal elctrode (the little bent part that creates the gap) is almost white

the center of the elctrode (the little part that makes the spark) is the size of a pin..I thought it was thicker when i put them in, but all that is left is the same size as the sharp point of a needle sticking out of the ceramic.


did I fry them??? could nitrous have done it so fast?
if you think it is the nitrous, i can use a larger fuel jet if it is running lean.

I can't get my digital camera to focus so close up so you can see all this..or I just can't figure the thing outChris Joohnson, JMS Chip and Superchips Custom Tuning almost took my head off when he saw i was running Denso's. He put NGK TR-6's in mine for street use, and it runs great. In my experience, Denso's run with nitrous are only reliable to 10,000 miles. They don't hold up as well to the pounding as do NGK or Motorcraft plugs. I am in the process of locating some race plugs that are 4 steps colder for nitrous (this would be an NGK R-10 or equivalent). Since I'm running a 300 hp shot, I will get dedicated race plugs for track purposes. As soon as I locate a proper set of plugs, I'll let you know what they are, and after I've taken them on 8-10 runs, I'll let everyone know how they perform and how they wear, with pictures.
It sounds like you are running a tad lean, and that happened to me when running the denso's wide open with the Zex kit. Up your fuel jet by two points (i.e. from a .20 to a .22), and this should fix the problem. If this doesn't do it, just increase the jet size by one and pull the plugs after 2 or three runs with the nitrous. Eventually, you'll find a mixture that runs just right. Good luck!

:banana2: :banana2:

[TAF]

Motorcraft cooler copper plugs (12C) is what has been recommended to me...and that's what I run.

[Fourth Horseman]

Motorcraft cooler copper plugs (12C) is what has been recommended to me...and that's what I run.

Same. Good results so far.

[CRUZTAKER]

I am done with densos as well.....

[1 BAD 03 MM]

No one had NGK TR-6's in stock, and I wanted to get some copper core plugs in. I went with the Autolite 103's. (1.89 ea) Full thread design. (They also have the 764's which are not the full thread design, but still copper core.) Both of these are cross references to the Motorcraft 12C plug

I replace my plugs every 12,000 mi. regardless.

FWIW, I ran the platinum tipped plugs that were stock in my 98 Taurus until 65,000 mi. Car was running bad, so took the plugs out.......they were gapped to 0.090. :eek:

(I did alot of research on said subject, and I will now run copper cores in everything, and change them often. Totally different than my oil change strategy.)

[Marauderjack]

I was worried that the Densos were bad as well but they looked fine (like new) when I removed them after about 6K miles?? ;) I will sell them to anybody interested for $30.00 shipping included!! :up:

I talked to many plug people and all said the NGK TR-6's are the best of the colder plugs with the NGK TR-6 IX (Iridium) the best for durability!! :rock:

The NGK rep said that Densos were a BIG problem in Mopar drag motors and the IX NGK's were the fix with no loss in HP?? ;)

BTW...The part number of the NGK TR-6 IX plug is 3689 and NAPA can get them for you!! :cool4:

Marauderjack :banana:

[SouLRioT]

the center of the elctrode (the little part that makes the spark) is the size of a pin..I thought it was thicker when i put them in, but all that is left is the same size as the sharp point of a needle sticking out of the ceramic.

FYI, not capable of answer any of your questions about plugs except that mine looked this way when they were new. On the box it even showed them having a smaller elctrode.

[Agent M79]

http://www.spark-plugs.co.uk/graphics/images/densoiridiumtip_t.jpg

[CRUZTAKER]

I always tell it like it is, no matter what the social results....
I am glad this thread has attracted attention, because somehow I was singled out as not liking the Densos and have had inuendos thrown at me like "the densos may not be right for you, but apparently they're good enough for others".
The beauty part, from folks that don't EVEN have a clue!:cry:

Voice your opinions folks, let it be known I'm not the only one who feels the c-note was a big waste of money...show you right!!!!:up:

[Agent M79]

...inuendos thrown at me like "the densos may not be right for you, but apparently they're good enough for others".

I think that happens because, more often than not, they are performing within expectation and people are happy with them.

Going strictly from memory, you are not the first to indicate function or longevity problems and highlighting the unacceptability of that in the face of the expense.

If I pay 3x, 4x, 5x the cost of a product compared to the nearest competitor, I expect more from the product. If the product turns out to be only as good as or lesser in quality to the "normally" priced product, then I am going to be just that much more upset.

Of course, I know Dennis specifically, if not all Denso dealers, will replace the plugs if they wear prematurely or otherwise don't function well.

As for me, because of you and the others, I am having my Densos pulled at my next service interval. They'll have 7000 to 8000 miles on them and if they exhibit more wear or problems than can be explained by my tuning then I'll replace them with something else. But, had no one said anything, I may not have had them pulled until their rated interval.

I'll post what I find here, good or bad.

[RF Overlord]

I'll post what I find here, good or bad.

Thanks, Agent... :up:

I have about 15,000 on my Densos (the car has 25,000); haven't pulled them out to look yet, but I also have no reason to...everything seems to be running fine...I was going to look at them when the car hits 30,000...

Is it possible that the Denso plugs show more of an improvement on a stock motor, or one that is only slightly modded? When the Densos first became available, there were relatively few members that had any mods beyond the chip and gears...now that it's been a while (like a year later), many have modified their cars to a much greater level and the 12Cs may now in fact be the better choice...

[TAF]

... and the 12Cs may now in fact be the better choice...Motorcraft AWSFA 12C are the plugs. Not easy to find...I special order through Team Ford. They run about $20 for 8 of them.

Some good reading here... http://www.crownvic.net/tech/sp_101.html

[Agent M79]

Motorcraft AWSFA 12C are the plugs. Not easy to find...I special order through Team Ford. They run about $20 for 8 of them.

Some good reading here... http://www.crownvic.net/tech/sp_101.html

Good article.

I will run the Densos till they need changing and swap over. Maybe get a set now as a "just in case" set since they are inexpensive.

Is it the #7 cylinder that sees the harshest conditions? Maybe spot check that one.

[CRUZTAKER]

Is it the #7 cylinder that sees the harshest conditions? Maybe spot check that one.
That's the one on mine that had no electrode left at 12k.
BTW: My car ran fine as well, one afternoon I was bored and pulled them out of curiosity.

[FordNut]

I will repeat what Mac said in an earlier thread. I wasted my money by purchasing another set. I pulled my first set after 20k mi and they looked just as good as the new ones that went back in.

[metroplex]

FWIW

The AWSFA-12Cs on my N/A 4.6 2V showed signs of electrode WEAR (there was a noticeable small angled part worn on the center electrode) at 10k miles/3 years of use. Basically the "flat square" corner of the center electrode is worn to a smooth finish and the part where the spark constantly jumps is very worn.

I'd estimate another 10k before absolutely needing to replace it due to an excessive gap that forms (total of 20k miles).

I am now using the AGSF-12FM1:
http://www.redpulsar.us/~coldfusion/film14/sparkcomparo.jpg

since they're OEM on Lightnings. Why is this a good reason? It's got to have met Ford engineering specs for longevity and performance - otherwise they would not have used them. :uzi:

[schuvwj]

FWIW

The AWSFA-12Cs on my N/A 4.6 2V showed signs of electrode WEAR (there was a noticeable small angled part worn on the center electrode) at 10k miles/3 years of use. Basically the "flat square" corner of the center electrode is worn to a smooth finish and the part where the spark constantly jumps is very worn.

I'd estimate another 10k before absolutely needing to replace it due to an excessive gap that forms (total of 20k miles).

I am now using the AGSF-12FM1:
http://www.redpulsar.us/~coldfusion/film14/sparkcomparo.jpg

since they're OEM on Lightnings. Why is this a good reason? It's got to have met Ford engineering specs for longevity and performance - otherwise they would not have used them. :uzi:


Metroplex what was the cost of the new AGSF-12FM1 vs the AWSFA-12C?

[duhtroll]

I just bought some 12Cs at $3.50 apiece, and that was without shopping around.

Don't know about the others.

-A

[Dennis Reinhart]

I am replacing my Denso IT-20 plugs with another kind... and when I took them out here is what I found..please let me know if it sounds like I am running too lean or rich and what other problems there might be...

I had 15,000 miles on them...and the last 100 miles I used a wet shot of nitrous at 75hp and only tried it for less than half a 10lb bottle...

I removed my Denso plugs and they were all in the exact same condition, absolutely no difference between cylinders...but here is what they looked like if I can describe them

at the base of the ceramic where it meets the metal (about the middle of the whole plug)..around the ceramic it is yellow/brown discolored.

the threads are light brown and the bottom of the threads the part in the cylinder has black soot on it.

the back of the metal elctrode (the little bent part that creates the gap) is almost white

the center of the elctrode (the little part that makes the spark) is the size of a pin..I thought it was thicker when i put them in, but all that is left is the same size as the sharp point of a needle sticking out of the ceramic.


did I fry them??? could nitrous have done it so fast?
if you think it is the nitrous, i can use a larger fuel jet if it is running lean.

I can't get my digital camera to focus so close up so you can see all this..or I just can't figure the thing out


It sounds as if they ran lean if you are using N20 I would try a copper plug call me tomorrow I will send you some for free, then I would get the AF checked on a dyno. I am not a big fan of N20 but I will be finishing the ZEX sytem testing this week if I use a system it will be a wet one, and gain I would never use N20 with out checking AF at WOT

[warren]

My 2 cents.

The Denso's are very unique-different iridium (w/rodium takes more heat) and have the smallest electrode to produce a bigger spark ball and more
power. Also will slow down knocking much better than any other plug....
This plug burns more of your fuel..... in our cars the PCM adjusts for this
by adding more and thus more power, milage & tq.

In a car using Nos. Ox. as in the Zex product your PCM does not have time
to adjust itself to to the need for more fuel because of short use so you must use a colder plug and raise the fuel nozzle a size ( If this is not done a lean condition would occur and make excessive heat ) as the Denso's are much more efficient in the burn process. The Zex info. should mention this. The next colder Denso plug is IT22.


WarrenB

[Agent M79]

As for me, because of you and the others, I am having my Densos pulled at my next service interval. They'll have 7000 to 8000 miles on them and if they exhibit more wear or problems than can be explained by my tuning then I'll replace them with something else. But, had no one said anything, I may not have had them pulled until their rated interval.

I'll post what I find here, good or bad.
I ended up having them pulled and inspected at 15,500 miles so they actually had about 12,000 miles on them.

They look good and went back in.

[RF Overlord]

Mine have been in for a little over 20,000 miles...car runs fine...unless there's an issue, I won't replace them until they're at 30,000...Dennis said they should last that long at least...