03 Accord V6 "needs" iridium plugs?

[clinebarger]

Originally Posted by Number_35
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.


Spark plugs are simple devices doing HARD work, People are quick to blame a product/manufacturer when something goes wrong. I'll never forget a truck that came in while I worked at the speed shop......They had put Vortec heads on a 350 Chevy & has "Ran like crap since Bosch plugs were installed", It had R45TS "style" standard reach plugs where it needed R44LTS6 "style" extended reach plugs.
I guarantee that the guy still thinks Bosch is junk because HE installed the wrong plugs.

Several other stories like just like that, This one sticks out in my memory for some reason?

Bosch is one of the few manufacturers that offers a WELL made universal O2 sensors with real long wire leads, I must have made over a thousand extended O2's for "long tube header" equipped Camaro, Mustang, & Ford/Chevy Pick-ups by installing the factory style connector.
I bet Bosch universal O2's have a bad reputation as well, Not because they're junk.....Because the average person is a Ignorant Hack with no tools to do the job correctly.

 

[JeffKeryk]

For some reason, Hondas run better with NGK or Denso. Doesn't really make sense to me; I have always been partial to Autolite.
I had a similiar thing happen on a Chrysler 4 banger back in the 90's. Installed Autolites and she ran poorly.
Dealer told me to use Champions, which I hate.
Champs made her run like a chanp. So from then on, I use OE plugs.

Iridiums are long lasting plugs and cost like $10.
I have never heard of blow-up-your-engine plugs...

 

[HowAboutThis]

I'd guess they last for 100k+ miles. Why not spend $50 and never worry about them again?

 

[clinebarger]

Originally Posted by JeffKeryk
For some reason, Hondas run better with NGK or Denso. Doesn't really make sense to me


Placebo effect at it's finest, I could install Bosch plugs in a Honda & it will run just fine.......As long as the owner/customer doesn't know it has Bosch plugs in it!!

Show me more data than "This plug runs better than this plug" with everything else being equal! Poor oscilloscope/burn time/KV waveforms?

The whole Allied Signal/Honeywell/Autolite restructuring thing might have something to do with you getting some bum Autolite plugs in the 90's....Where I'm confident that ANY well made/correct plug would have worked just fine in your Chrysler product!!!!!!

 

[columnshift]

Wow, BUCKETS of responses here vs nothing on the honda boards. I love this place.

Originally Posted by SatinSilver
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.


Originally Posted by Warstud
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.



There's enough doubt here that I think i'm going to go with factory OEM - I still dont know if that is Denso or NGK though! :-/ Some people say Bosch is fine, others express doubt, but especially if this is a PITA to even put in i'll take the high road spending a few more getting factory suggested iridiums and hopefully not worry about it again.



Originally Posted by chrome
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.



Autozone wont let you OBD the car yourself (or they wouldnt at that location), the guy wouldn't even give me the actual code - he just punched the code into his computer with suggested mileage which I told him was 175k (which I think is about right) and their computer told him "replace spark plugs" and nothing else. I asked original owner, he said he didn't remember anything about plugs ever being done (at least not recently) and i've no clue what the recommended life or service change intervals are... so i'm just going to pull and replace them. I'll get pictures and post them here and ask for help since i'm no plug reading expert.

If I have the misfire afterwards though, what would the next step be, replacing coils? I'll try to get the exact code too. (at least ORielly's will let me handle my own dang OBD2 scanner )

 

[chrome]

No, don't throw parts at the problem. You need proper diagnosis to see why the misfires are happening. Each cylinder needs spark, compression and fuel to run. You need to identify which basic element is missing.

Plugs on the front bank is easy, rear bank needs more effort, contortion and articulation due to the tight space but doable if you have the correct 3/8" socket extension length which is not too long or short.

Since you have misfire code for cylinder 6, I would suggest pulling plug 6 (front bank on right side, away from timing belt) and look at the condition of the plug, then decide.

 

[ctechbob]

Its worth the $10 (about $5ea) to ebay a bluetooth OBDII dongle and an app from the app store (Torque etc). You'll not have to mess with the autoparts stores and reading codes again.

Plugs should be done every 100k on the J Series and yes the Denso's are probably the best bet. As for a #6 misfire, what has been said above, pull the plug and look and/or swap a coil from one plug to the other and see if the misfire moves. Not unheard of for a coil to go funky.

 

[Trav]

Originally Posted by clinebarger
Originally Posted by JeffKeryk
For some reason, Hondas run better with NGK or Denso. Doesn't really make sense to me


Placebo effect at it's finest, I could install Bosch plugs in a Honda & it will run just fine.......As long as the owner/customer doesn't know it has Bosch plugs in it!!

Show me more data than "This plug runs better than this plug" with everything else being equal! Poor oscilloscope/burn time/KV waveforms?

The whole Allied Signal/Honeywell/Autolite restructuring thing might have something to do with you getting some bum Autolite plugs in the 90's....Where I'm confident that ANY well made/correct plug would have worked just fine in your Chrysler product!!!!!!


+1 you cant argue word of mouth, service advisors or you tube videos here, they are gospel. Proof? Who needs proof when joe smuckatelli said so.
The Bosch OE fine wire is German made and they warranty the iridiums for 7 years but that's still not good enough for some people.

Bosch OE

 

[Schmoe]

All I've ever used on my V6 was NGK plugs. Never any issues and can go comfortably to 105K miles.

 

[meep]

I've got to say, I always liked bosch plugs in my cars, but I too watched a new set of bosch plugs cause a rough idle in a '89 accord. My brother gave up on it, the dealer told him to change the plugs before bothering to bring it in. He put something else in there and the rough idle resolved. I've used bosch in two of my subarus, a nissan, a chrysler, with no problems, and that includes multi-electrode style plugs. That accord didn't like them. Not placebo.

 

[StevieC]

Bosch has their place as do NGK and Denso. This being a Honda I would recommend NGK/Denso because it most likely came with either and from my experiences these have worked out better in Japanese vehicles than Bosch or Autolite or Champion or other brands.

 

[Whimsey]

While it's not an Accord, our 2017 Explorer with the 2.3 EB uses Motorcraft branded NGK iridium plugs. Ironically they are less expensive than the equivalent NGK brand plugs, $4.50 vs ~$7.50 , go figure. Also, thank goodness the engine is an inline 4 cylinder with real easy access to the plugs

.

Whimsey

 

[Trav]

Probably the wrong heat range, I bet they were not the OE fine wire.

 

[kr_bitog]

The oe fine wire is working well as ngk or denso, however bosch ceramic as not as good, i have one bosch that broke the ceramic and one that failed to spark in less than a year.. denso and ngk is more durable as long as you dont get counterfeit

 

[nthach]

Originally Posted by Trav

+1 you cant argue word of mouth, service advisors or you tube videos here, they are gospel. Proof? Who needs proof when joe smuckatelli said so.
The Bosch OE fine wire is German made and they warranty the iridiums for 7 years but that's still not good enough for some people.




An ex-friend has these in his truck that Midas installed. When I saw Bosch on on the insulator my first instinct was to remove them but turned out they are the OE fine-wire design and not the original Platinum design with a tapered tip. I left them in, truck was running just fine after I took care of the wires and cam/crank corelation.

 

[slacktide_bitog]

I know most people don't like the Bosch gimmick aftermarket Platinum+2 and the Ir Fusion (in fact, I don't think Bosch even makes them anymore), but one place they really came in handy was Toyota's 1MZ engine. The 1MZ came with NGK or Denso 2-prong platinum plugs that cost about $10 each, and they were only platinum, not iridium, so they're only good for 60k.

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! And the ONLY iridium multi-prong available was the Bosch Platinum-Ir Fusion. Iridium is good for 100k, and the Ir Fusion has 4 prongs. So if you use those, and also replace the valve cover gaskets, you won't have to do the job again for a LONG time!

Normally you want to avoid those aftermarket Bosch plugs, but the 1MZ is a major exception!

But for the OP's Accord, just use the OE Denso or NGK Iridium

 

[BAJA_05]

NGK Laser Iridiums

 

[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.

 

[bbhero]

Originally Posted by Trav
Probably the wrong heat range, I bet they were not the OE fine wire.



I bet you are right here Trav. Heat range does matter a whole lot... Funny deal with my car.... The Bosch fine wire iridium plugs recommend by AAP and AZ do not match the ones recommend by Federal Mogul. The ones they recommend are $10+ a piece and a different heat range... Something tells me that the ones offered up from AAP and AZ are not right at all.

 

[clinebarger]

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.


Specific plugs are specified for EVERY engine, The argument here IS.....Can a manufacturer that did not make the OE plug make an exact copy of the plug the engine calls for?