03 Accord V6 "needs" iridium plugs?

[nthach]

Originally Posted by bobdoo
"Ion sensing ignition"...

Newer engines analyze the current flow *during* ignition and combustion. This requires a specific, narrow range of plug resistance to perform correctly. That also includes resistance due to tip shape/sharpness, gap, and metal conductivity. That's why some specific plugs are mandated in the owner's manual.

Saab pioneered that concept in the 1990s - Trionic also needed a special coil pack and other ECU/PCM magic to make ionization detection possible. GM didn't take Trionic outside of Saab and maybe Opel.

Yes, you need plug resistance - but that's to help keep RF interference down. I've broken the "OEM plug supplier" rules more than once - I've installed Denso and NGK into a pair of Mercedes V8s my parents had - cars ran fine. I've threw Champion Platinums into a Toyota. Except for a persnickety few cars on the road that must use the OEM plug(as well as Mazda rotaries and Toyota D4-S engines that use a special tri-electrode Denso plug), you can get away with an aftermarket plug that isn't a gimmick like the original Bosch Platinums/Splitfires/E-3.

 

[columnshift]

Whelp... I returned the Bosch's and got some NGK Laser Iridiums for $10 each and took about 2 hours to put them in cuz that rear bank sucks... didn't seem to dramatically change the running.

I will post pictures of the old plugs when I get a chance... for some reason there's Autolites in there, so they must've been done on the cheap at some point but normally the guy did it at the Honda dealership, hmm... none of the plugs seemed terrible to me, but regardless I shouldn't have to touch plugs again for the expected life of the car. (if I get 60-80k out of things reliably i'll be pretty happy)

So tomorrow i'm going to grab some coils. To those mentioning #6... it's actually three misses... #1, #3, and #6 are all missing CONSTANTLY whether idle or high load or slow load. None of the plugs looked so bad as to have obvious misfire reasons that I could tell. (gaps looked a bit worn but no horror shows even a nonmechanic would notice)

But should I go factory coils, or whatever off brand Orielly and Autozone have to save a few bucks? Is this another case of "stick to OEM!" where Honda's are sensitive?? I'm already $60 in for plugs (plus some tools) and 3 coils are either $105 or $150 depending which I get.

 

[The Critic]

Originally Posted by columnshift
Whelp... I returned the Bosch's and got some NGK Laser Iridiums for $10 each and took about 2 hours to put them in cuz that rear bank sucks... didn't seem to dramatically change the running.

I will post pictures of the old plugs when I get a chance... for some reason there's Autolites in there, so they must've been done on the cheap at some point but normally the guy did it at the Honda dealership, hmm... none of the plugs seemed terrible to me, but regardless I shouldn't have to touch plugs again for the expected life of the car. (if I get 60-80k out of things reliably i'll be pretty happy)

So tomorrow i'm going to grab some coils. To those mentioning #6... it's actually three misses... #1, #3, and #6 are all missing CONSTANTLY whether idle or high load or slow load. None of the plugs looked so bad as to have obvious misfire reasons that I could tell. (gaps looked a bit worn but no horror shows even a nonmechanic would notice)

But should I go factory coils, or whatever off brand Orielly and Autozone have to save a few bucks? Is this another case of "stick to OEM!" where Honda's are sensitive?? I'm already $60 in for plugs (plus some tools) and 3 coils are either $105 or $150 depending which I get.


If you have access to a scan tool, what does the MAP voltage read at hot idle? If it is more than .9-.95v, you probably have a valve adjustment issue.

The plugs on the rear bank can be done fairly easily if you use two separate 3" extensions.

 

[slacktide_bitog]

Originally Posted by columnshift
Whelp... I returned the Bosch's and got some NGK Laser Iridiums for $10 each and took about 2 hours to put them in cuz that rear bank sucks... didn't seem to dramatically change the running.

I will post pictures of the old plugs when I get a chance... for some reason there's Autolites in there, so they must've been done on the cheap at some point but normally the guy did it at the Honda dealership, hmm... none of the plugs seemed terrible to me, but regardless I shouldn't have to touch plugs again for the expected life of the car. (if I get 60-80k out of things reliably i'll be pretty happy)

So tomorrow i'm going to grab some coils. To those mentioning #6... it's actually three misses... #1, #3, and #6 are all missing CONSTANTLY whether idle or high load or slow load. None of the plugs looked so bad as to have obvious misfire reasons that I could tell. (gaps looked a bit worn but no horror shows even a nonmechanic would notice)

But should I go factory coils, or whatever off brand Orielly and Autozone have to save a few bucks? Is this another case of "stick to OEM!" where Honda's are sensitive?? I'm already $60 in for plugs (plus some tools) and 3 coils are either $105 or $150 depending which I get.


The NGK Laser Iridiums will last at least 100k with no problem.

The Denso coils on Rock Auto are the actual OE coils at a much better price than the dealer

 

[clinebarger]

Originally Posted by slacktide_bitog

But doing a spark plug job on the 1MZ is almost impossible. Getting access to the rear bank, pulling the intake takes a whole day by itself!


It's not that bad, While not an easy job.......I can do valve cover gaskets & spark plugs on a 1MZ-FE equipped Camry/Avalon in @ 6 hours including resealing all 4 cam plugs & changing the spark plug tube seals.
You must be disassembling to many components.....
*Leave the vacuum solenoids attached to the upper intake.
*Only remove the 2 10mm headed nuts on the EGR pipe, No need to to remove the EGR valve/stand from the upper intake.

 

[columnshift]

Originally Posted by slacktide_bitog

The NGK Laser Iridiums will last at least 100k with no problem.
The Denso coils on Rock Auto are the actual OE coils at a much better price than the dealer

I have to drive 600 miles on friday. Wont I hurt the catalyst if it's throwing NONSTOP codes from misfires on 1/3/6?

I see Denso for $58 on rockauto, low as $14 for their economy stuff... but is there a big quality difference? I'm almost wondering if junkyard pulls be worth the risk, I dont know how long coils normally last or if thats as silly an idea as used spark plugs though...

...and is this something I should replace all six at once (like plugs) cuz the others probably going out soon after or just those misfiring? Sorry if i'm a dummy but i'm not a mechanic just a tinkerer.

EDIT: someone just pointed out all six coils on amazon for less than even rock auto https://www.amazon.com/Pack-Ignition-Coils-Honda-Compatible/dp/B00P34B6GA is there any reason this would be a bad choice? Reviews arent crap, trying to avoid a $300 parts bill too... unless I hear strong advice warning away I may be plunking that in the next 23 hours and ship to my halfway destination. (after 300 miles of stumbling, I can install them there to hopefully run on the way back with less stress on the catalyst from assumedly unburned fuel)

 

[columnshift]

Originally Posted by The Critic

If you have access to a scan tool, what does the MAP voltage read at hot idle? If it is more than .9-.95v, you probably have a valve adjustment issue.

The plugs on the rear bank can be done fairly easily if you use two separate 3" extensions.


The only scan tool I have is to borrow the OBD2 from like an Orielly's or something, will the MAP voltage automatically read out on some page of data or do I have to tell it to display specific data? I've no clue what specific scan tool they have that's just all I have access to for now... (i'll eventually get a bluetooth reader but don't have one yet) Is more than the .95 going to throw a different code warning of valve issues?

I just find it so strange that it's consistently 1/3/6 misfiring when on a previous drive (a few weeks back) I drove all over town dozens of miles without the slightest missed step. Something just decided to crap out between now and then...

 

[chrome]

Originally Posted by columnshift
So tomorrow i'm going to grab some coils. To those mentioning #6... it's actually three misses... #1, #3, and #6 are all missing CONSTANTLY whether idle or high load or slow load. None of the plugs looked so bad as to have obvious misfire reasons that I could tell. (gaps looked a bit worn but no horror shows even a nonmechanic would notice)

But should I go factory coils, or whatever off brand Orielly and Autozone have to save a few bucks? Is this another case of "stick to OEM!" where Honda's are sensitive?? I'm already $60 in for plugs (plus some tools) and 3 coils are either $105 or $150 depending which I get.


Are you going to parts cannon the problem? If you have a misfire consistently on #1, 3 and 6, and #6 is easy to access, it would make sense to swap #6 coil with #4 or #5 on the front bank, and see if the misfire moves. This is where a small investment in a scan tool is invaluable to diagnosing a problem.

Don't drive the 600 miles with so many cylinders misfiring, you will melt the catalytic converter in no time.

 

[BAJA_05]

For $58 bucks and FREE SHIPPING for a pack of 6 -- replace them all at one shot. Car is 15 years old with almost 180 thousand miles --- give you a piece of mind at the least.

Ps. I would not attempt to drive that many miles with misfires neither.

 

[BAJA_05]

I checked your link on Amazon -- make sure your getting the ones that you have linked and not the $59.99 ones. The $59.99 ones are not made for your specific Accord years with that engine 3.0L -- the link that you posted on this thread are the ones you want.

 

[columnshift]

Originally Posted by chrome

Are you going to parts cannon the problem? If you have a misfire consistently on #1, 3 and 6, and #6 is easy to access, it would make sense to swap #6 coil with #4 or #5 on the front bank, and see if the misfire moves. This is where a small investment in a scan tool is invaluable to diagnosing a problem.

Don't drive the 600 miles with so many cylinders misfiring, you will melt the catalytic converter in no time.


Good point. I said i'm not a mechanic. I'll try swapping coils around. Does anyone know the cyl numbering for sure? Random online searches suggest when i'm facing into the engine 1-3 from left to right in the back, and 4-6 along the front from left to right.

And to the next person yeah there was a less expensive coil set but it would take longer to get to where I needed to be so I was skipping it. (though it also claimed to be for the same engine) I was only referring to the EXACT link at amazon right now trying to get things sooner.

 

[columnshift]

Okay I swapped coils around - 1/2, 3/4, 5/6 (with the original misfires on 1, 3, and 6). Now i'm getting misfires on 2, 3, and 5. I'm a little baffled by the misfire on 3 and why 4 would NOT be misfiring now... but the other two make sense - crap coils seem to be a part of the problem. I just ordered the pack of six to arrive saturday and cancelled my 600 mile trip so I dont' damage the engine. I'll follow up then.

This said... does it make sense that suddenly 3 or 4 of the coils would poop the bed out of the blue when a few weeks ago it was throwing no codes and running sweet and smooth? (the whole reason I bought this car) That seems statistically unlikely...

Also i'll get up plug pictures this weekend too.

 

[nthach]

Two possibilities I can think of - either the 5th cylinder has bad wiring for the coil or an injector is acting up. But I think if an injector went out an injector code for that cylinder(P020x) for open injector circuit would also be thrown as well. Injectors can still fail with a good coil(the injector one - it's a solenoid after all) - the pintle valve can "freeze" shut.

Were the valves ever adjusted? I'll leave the rest for Trav and clinebarger to spitball.

 

[Daverino]

I have heard that the OEM supplier to Honda/Acura of COPs is Hitachi. The ones I have seen are labeled as "Made in Japan". Use some dielectric grease as well. If you are looking to save some money then that is where I would look, I would not even consider the parts store stuff.

The OEM specified spark plugs are Iridium and Platinum, from NGK most likely. I think that NGK sells a lesser model that leaves out the Platinum side and does not have the longevity.

Are all three malfunctioning cylinders on one head/side of the engine? I should know this, but forgot.

These engines also need to have their valves adjusted. Some do it every 105K with the timing belt, others do it only when the engine has a problem. I would do it now as you have obviously have a problem and throwing "good idea" maintenance at a car is always a good idea. Throwing cheap non-standard parts at a car with problems is not a good idea.

When you have the intake off be sure to clean the throttle body without moving the butterfly valve. And clean out the EGR passages as this is an area that can be a problem on high mileage J series V6s.

 

[columnshift]

Whelp... replaced the 6 ignition coils with those I ordered for $69 from amazon - and the misfires all went away. No more codes thrown at least over engine misfires - idles smooth, drives smooth, power back. (at least not yet, in the 10min drive home, i'll see more this week) However I DO think the plugs were a contributing factor... weak coils plus perhaps dodgy spark plugs up in age both a part of it.

So lets look at some plugs - because I dont honestly really know how to read them.

I'm sorry for the crappiness of my pictures and organization, I should have labeled the plugs as they came out but I was working in cold rain at night trying to get things in (in a desperate attempt to make my 600 mile trip the next day - which I had to cancel not wanting to damage the car) so i'm not 100% which came from which cylinder right now... but if any look particularily horrible I can try and line up my multiple pictures (others I didnt link, these are crops) with how I laid them out on the engine to maybe figure it out.

https://www.dropbox.com/s/ws26078tsejfx4n/lower3.jpg?dl=0
https://www.dropbox.com/s/uqi19m6wllsu5v0/upper3.jpg?dl=0
https://www.dropbox.com/s/vp3cchk0es15lsk/2018-09-26 20.06.44.jpg?dl=0
https://www.dropbox.com/s/wbt4nk0czsjvkoz/2018-09-26 19.54.44.jpg?dl=0
https://www.dropbox.com/s/qz2zrfl9q3ghaid/2018-09-26 19.54.54.jpg?dl=0
https://www.dropbox.com/s/oq5kr6kiax6c7tf/2018-09-26 19.26.06.jpg?dl=0
https://www.dropbox.com/s/cugxqk1ox9hhpyz/2018-09-26 19.25.55 plug1.jpg?dl=0
https://www.dropbox.com/s/ivgmkfu8w5l1389/2018-09-26 19.24.50 plug3.jpg?dl=0
https://www.dropbox.com/s/s54fqixmkme3dh4/2018-09-26 19.24.03 plug2left plug3right.jpg?dl=0

 

[columnshift]

Originally Posted by nthach
Two possibilities I can think of - either the 5th cylinder has bad wiring for the coil or an injector is acting up. But I think if an injector went out an injector code for that cylinder(P020x) for open injector circuit would also be thrown as well.


Well it seems to run fine after new good plugs and new coils, so hopefully I wont need to touch other things for awhile.


Originally Posted by Daverino
I have heard that the OEM supplier to Honda/Acura of COPs is Hitachi. The ones I have seen are labeled as "Made in Japan". Use some dielectric grease as well. If you are looking to save some money then that is where I would look, I would not even consider the parts store stuff.


Consider the parts store stuff of what, dielectric grease? I used the dielectric grease included with the coils.


Originally Posted by Daverino

The OEM specified spark plugs are Iridium and Platinum, from NGK most likely.

Are all three malfunctioning cylinders on one head/side of the engine? I should know this, but forgot.


I went with NGK Laser Iridiums, apparently the OEM suggestion. What was in there was some Autolite stuff which i'm scratching my head at, since I thought all work on this car had been done at a stealership before.

And no, two were in the back and one was in the front. It really did seem to be some mix of coils and plugs, because i'm not so sure about the plugs which I linked pictures to above for anyone curious or wanting to suggest things to watch or inspect for other future maintenance.

Originally Posted by Daverino

These engines also need to have their valves adjusted. Some do it every 105K with the timing belt, others do it only when the engine has a problem. I would do it now as you have obviously have a problem and throwing "good idea" maintenance at a car is always a good idea. Throwing cheap non-standard parts at a car with problems is not a good idea.

When you have the intake off be sure to clean the throttle body without moving the butterfly valve. And clean out the EGR passages as this is an area that can be a problem on high mileage J series V6s.


I'm assuming if it was scheduled at 105k it should have been done by the dealer. I think the guy took pretty good care of the car getting things done on time. I'm all for good idea maintenance, I just need to be better set up to do it myself - which I wont be until spring/trying to avoid most other work until spring or summer. Dealing with endless RL crises which wont let me focus on the car esp as it gets colder. If I make it until then I hope to catch up on whatever 'should' be done.

I went with OEM plugs and cheap amazon coils that at least instantly fixed the problem with a warranty. (not in a position to drop $400 on factory coils, $70 is about what I had and it was enough) I didn't have the intake off (i'm guessing thats for valve adjustment?) or do any valve adjustment - hopefully I can do that come spring or summer if I make it through this winter's other crises. (family health problems, broken furnace in house, other things not worth getting into...) Then I can catch the car up. Do you have recommended resources on how to do those things handy by chance? Vids or whatever. I've never had this series Honda or engine before so i'm not too familiar with what it needs to hopefully last another 60/80/100k. (i'm assuming the 5 speed auto will die somewhere in that figure - it was either replaced or rebuilt at 105k but since i'm 75k into miles after that, i'm assuming the remaining life of that trans is probably from 60-100k? so am just trying to pace other things to match)

 

[clinebarger]

Originally Posted by columnshift

I'm assuming the 5 speed auto will die somewhere in that figure - it was either replaced or rebuilt at 105k but since i'm 75k into miles after that, i'm assuming the remaining life of that trans is probably from 60-100k? so am just trying to pace other things to match


The MAYA/BAYA units in these cars are a disaster on wheels. Poor Cooler Flow is the #1 killer of these units from improper pressure regulation balance.
Causes a domino effect that trashes the converter from TCC Drag as there is not enough TCC release pressure without cooler flow, Frictions that already have poor lubrication to begin with fail......Third Gear frictions in the case of the 5-speed units.

Unfortunately......Not really anything you can do about it as corrections require removal & disassembly of the unit. ONE thing you could do to prolong the life of this unit IS.....Do Not let it idle for prolonged periods of time at operating temperature!

I have performed cooler flow tests on these & sister units in the Odyssey/Pilot, Cooler flow Reduction/Temperature Spike happens at idle speeds. The SMALL fixed displacement gear pump is very inefficient at lower speeds & has ZERO reserve capacity. Raise engine RPM above @1200 RPM & Cooler Flow returns!

 

[BAJA_05]

AWESOME news with the coils you ordered matched with the NGK Laser Iridiums working out for you. Hopefully no codes appear in the near future -- which I do not see happening pertaining to the coils or plugs. Good thing you changed the plugs, engine is thanking you going with the plugs you installed.

 

[BAJA_05]

Also, couple drain & refills on that Tranny paired with a good Fuel System Cleaner like Chevron Techron Complete Fuel System Cleaner or Regane High Mileage Fuel System cleaner -- you will be good to go!!!!

 

[nthach]

On Hondas, a spill and fill of the ATF every second OCI doesn't hurt - use Honda DW-1 fluid if you like the OEM shift feel or MaxLife if you want something that's a full "synthetic" and a little bit of a firmer shift.