03 Accord V6 "needs" iridium plugs?

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So I acquired on short notice (didnt have time to properly inspect/"needed a car by this monday" literally) a 2003 Honda Accord V6 EX with about 170-180k on it from a guy I knew and had helped work on this car before. 15 miles down the road while taking it home it suddenly does a stumble-jerk dropping in RPM, then throws a code. Periodically re-stumbles and re flashes the check engine light.

Stop at an Autozone, the code says "replace spark plugs" and says misfires on 1/3/6 repeatedly but doesnt say any bad sensors. I'm not sure when plugs or wires had been replaced last. (and cant ask him for a bit/he was heading out of town right as I got the car)

He gives me this ultra hard sell about iridium plugs saying anything else will destroy my engine guaranteed and they wont even sell me plugs that arent iridium so I pick up some bosch but didn't yet install. I hear others say NGK or Denso may be the original equipment ones but didn't know if that matters, or which it would have been.

Is it true that non iridium plugs could 'destroy an engine' and how, pray tell? I would have thought plugs are plugs, they either ignite the mixture or they dont, they either miss or they dont. The only difference is how long they last. I wonder if this is like that $30/gallon blue coolant (which I look at with a jaundiced eye and somehow doubt is essential, or if they engineered it so it is makes me think thats an extortion strategy) or if there's a legitimate reason to go iridium.


Also seeking advice on plug wires - I dont know when they were replaced but figured i'd just get them too, and dont know if I need some OEM or higher quality or if less expensive is good enough for this car.
 
Return the Bosch plugs. For some reason they can cause drivability issues esp in Hondas. Buy some NGK plugs from www.rockauto.com for a good price. Stick with Iridium plugs.
 
Go to Honda forums. There's a TSB 04-042 having to do with updating computer to fix codes P0301, P0305, and / or P0302, P0306, and possible P0300.
 
Did the car come with an owner's manual? What does that say? I'm no Honda expert but I've never heard of a car REQUIRING iridium plugs. I can't image how using anything else would/could damage anything.

I do agree about returning the Bosch plugs and getting NGK or Denso.
 
Not using Iridium plugs will not destroy an engine. Could it make it run less efficiently maybe, but not destroy it.

I would also go with NGK or Denso in your Honda and not Bosch. JMO.
 
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Iridium plugs will last longer than copper plugs but copper perform better. I would only use iridium is if the plugs are hard to get at .
 
This engine uses COP (coil on plug) so double precious metal plugs are not a necessity and no harm will come from not using them. That being said if they sold you Bosch 9614 plugs they are a very good plug and there is no need to return them.
There is no advantage whatsoever going with NGK, Denso or a any other brand.

Edit: Copper does not perform better, most if not all plugs inc platinum and iridiums have a copper core, the firing voltage of precious metal tipped plugs is lower and in fact provide better performance and easier starting. This can be proven by putting a platinum plug in OPE engines, they start easier and run smoother with lean running al gore carbs.
 
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This is not applicable to this engine or most non forced induction engines. They will help prevent detonation in high boosted engines at the expense of longevity.
It doesn't mean they perform better in all applications only very specific ones.
Good lord if you tube ever goes under many people on this board would be lost, if its on you tube it must be true.
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The Honda service manager here has said not to use Bosch plugs. They've had cars come in with issues and the Bosch plugs were the culprit. The owners manual says something along the lines of using Denso or NGK for optimum performance.
 
Originally Posted by Trav
This is not applicable to this engine or most non forced induction engines. They will help prevent detonation in high boosted engines at the expense of longevity.
Why is that? I understand the wasted spark and transverse engine arguments for iridium or double platinum but not this one.
 
I sell spark plugs all day long.

There is NO REASON you HAVE to use Iridium plugs. However, you will experience a shorter lifetime of the plug and need to change it sooner.

And BOSCH plugs SUCK for anything other than where they are OE specified. Get either NGK or Denso for the Honda!
 
You definitely do want to use iridium on a transverse V6! Most of them are very difficult to do trying to get to the back row.

Honda seems to be one of the better designs where you can replace the rear plugs without pulling the intake, but still, iridium is still s good idea. NGK Laser Iridium, Denso Iridium Loing-Life, or Iridium TT.

In regards to the coolant, Napa and Advance have Pentofrost A3 for about $15/gal. Walmart has Zerex Blue for $11. Pep Boys has Recochem OEM Blue for $20 (and this one is a concentrate, and on top of that, Pep Boys often puts the Recochem on sale). Peak Global Lifetime is also good stuff.

I don't think your V6 has wires. It is most likely coil-on-plug.
 
Originally Posted by SatinSilver
The Honda service manager here has said not to use Bosch plugs. They've had cars come in with issues and the Bosch plugs were the culprit. The owners manual says something along the lines of using Denso or NGK for optimum performance.


Every manufacturer recommends a certain brand plug. Bosch makes as good a spark plug as anyone in the business!! I can guarantee that if the correct Bosch plugs are installed correctly......You wouldn't notice a difference.
 
Originally Posted by SatinSilver
The Honda service manager here has said not to use Bosch plugs. They've had cars come in with issues and the Bosch plugs were the culprit. The owners manual says something along the lines of using Denso or NGK for optimum performance.

Yep....take them back. Why take the chance...go with OEM so you don't have to do the job twice.
 
The best automotive advice I ever received was that unless there's an overriding reason to change ( engine mods or whatever ), stay with the OEM plugs...it's the trade off of actually "needing" them versus the "need" to have to replace them or having issues arise because you put in something else to save a few bucks or it looked like "it would work just as well".
 
Originally Posted by columnshift
Stop at an Autozone, the code says "replace spark plugs" and says misfires on 1/3/6 repeatedly but doesnt say any bad sensors. I'm not sure when plugs or wires had been replaced last. (and cant ask him for a bit/he was heading out of town right as I got the car)


I don't think there is a specific code that says "replace spark plugs". That is probably just a recommendation based on the misfire codes. You have a misfire on cylinders 1, 3 & 6 which is spread across both front and rear banks. Apart from spark plugs and coils, there could be other contributing reasons for misfires on both banks. Check for vacuum leaks and fuel pressure too if new plugs do not resolve the issue.
 
I was about to second what several previous posters have said, which is to stick with NGK or Denso for a Japanese or Korean engine, but I have great respect for Trav and Clinebarger. If they say Bosch is OK, I'd feel fine about using them.

The linked thread from a couple of years ago is w.r.t. plugs for my '09 Kia Sedona:

[

NGK customer service recommended the top-line iridium plugs for best life (120K km). I don't think there would be any harm in running a lesser (G-Power or platinum) plug, only that for a transverse DOHC six I have to pull the intake manifold, which I hope to do as few times as possible!
 
What is OE? I have done Honda engines with originally installed NGK on one bank and Denso on the other. I have a Hond running around with 70K miles on Bosch OE fine wire iridiums.
Made in Germany and a nice heat range for these engines
 
Originally Posted by maxdustington
Originally Posted by Trav
This is not applicable to this engine or most non forced induction engines. They will help prevent detonation in high boosted engines at the expense of longevity.
Why is that? I understand the wasted spark and transverse engine arguments for iridium or double platinum but not this one.


Good explanation in the link below. I run high boost pressures with ice cold NGK copper plugs and wires in a GM, longevity is very low but they work well. I don't agree with keeping plugs in house eg Delco in GM (they are NGK anyway) or NGK in Japanese. Heat range and proper fit is more important than brand. Find OE for an old air beetle or Citroen, you cant, Beru hasn't made a plug in decades and they were one of the largest providers of OE ignition parts for Euro cars back then. All that exist of Beru is the name they are owned by BorgWarner.

http://www.superchargersonline.com/index.php?main_page=page&id=27
 
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