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My 04 r6 started running like crap last time I had it out. Below about 5k it was sputtering and missing. It also is idling lower than usual and is stalling out on idle. I've read through the forum a little and it seems like the first place to start was the coil packs. I tested them today and had the primaries test out of spec between .5 and .6 ohms. The secondary's all tested within spec at 5.75 to 5.9 ohms. My main question is are the primaries out of spec enough to cause the problems I've described? I would just like to figure out if this is the problem before I drop $200 on new ones. Thanks
 

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Just started experiencing the same issue on my 05, and my coils are reading the same as yours. Visual inspection of the plugs looks good (reddish brown). Curious if anybody has an answer to this?
 

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I miss Cali rides :/
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spray water on each of your header pipes. the one that doesnt boil away instantly is the culprit. if you are on a tight budget, ebay is your friend. on mine, iirc, the resistance was good or very low difference and no signs of burning at all. just all of a sudden one day, bam, no worky.
 

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There was a recall on the ignition coils back in 2003/2004 for these bikes. I had to replace mine. See if you can find someone on here with a working set. I'm not sure that's the exact problem, but it sounds like it.
 

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click, click, vroom!
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do what brandx73 said as a quick test, that will usually tell you where the problem is. fire up the bike and let it idle until it warms up, then hit each header with mist from a spray bottle and see which pipe is cooler. that's the problem. you don't need to buy a full set if one is bad, just replace the bad one(s). i've got a few spares if you need a deal on one or two, PM me if you need 'em in case i don't find my way back into this thread.
 

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Update*

Was forced to put the bike back together (waiting to buy coils) since my car is in the body shop for repairs. Ended up replacing the spark plugs since I had everything apart and noticed the PO pretty much finger tightened the last set of plugs on. Took the bike into work and it's running fantastic now; much smoother than I remember with no hint of misfire. Seems this may have been my problem after all.
 

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My 04 r6 started running like crap last time I had it out. Below about 5k it was sputtering and missing. It also is idling lower than usual and is stalling out on idle. I've read through the forum a little and it seems like the first place to start was the coil packs. I tested them today and had the primaries test out of spec between .5 and .6 ohms. The secondary's all tested within spec at 5.75 to 5.9 ohms. My main question is are the primaries out of spec enough to cause the problems I've described? I would just like to figure out if this is the problem before I drop $200 on new ones. Thanks
Did u fill up recently? Could be bad gas. How do ur spark plugs look? When did u change them last? Are u experiencing power loss when riding? How does ur filter look?

As long as they all read close to each other, they are fine. If u do have a bad one it would be way out of spec and way obvious. Also before u determine that they are out of spec make sure u get specs for the correct year ( call the dealer they can look it up) Also a coil can be with in spec and still not work, I had that happen on my '05. Inspect the body of the coil carefully. If the housing of the coil goes bad ( burns or cracks) it will arc everywhere but on the plug resulting in the cylinder not firing.

And yes the '03/'04 did have a recall on them so call the dealer and give them ur vin, they will tell u if urs has a recall.
 

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I have this exact same issue in this post. This just started for me this week. Some background:
I changed my plugs (or my bikeshop friend did) back in March. I haven't been able to ride a whole lot this year. The other day I rode to work, no problem. I went to leave and instantly my bike sputtered at low speeds. Once I got over 50mph or so it was fine. I even gassed up and had a friend test it out and they noticed it was bad also. Immediately we thought coils.
Well I finally got the coils off today and checked the resistance of them. All checked out fine. We pulled out 2 plugs (I can't get to the other 2 yet) but noticed the two plugs didn't look the same. The first one was pretty clean on the threads but was dark brown/black at the tip. I figured that was normal. The other plug though, different story. The other plug did not have clean threads. It actually looks like oil or something is on the threads. We thought this was bad! I have heard that new plugs could be bad... so I'm not sure if that is my case? I know when my plugs were put on he did not use a torque wrench, but by feel. He said he has changed LOTS of plugs at the shop, so I trusted him (rightfully so, he has tons of knowledge and knows what he is doing). So... after all of that... is it possible I have a bad plug due to bad gap or something? Is it possible that I have bad coils still even though resistance is ok?
Lastly, I did the recall check for my bike and no go. I do have the Denso coils, but they told me they had to have been installed aftermarket. I am obviously not the new owner.
My main thing is that if we changed the plugs a few months ago... how could they just now be bad? IF it wasn't gapped right or installed right, wouldn't we notice it right away?
Visually also my coils look fine. HELP! and thanks.




Update*

Was forced to put the bike back together (waiting to buy coils) since my car is in the body shop for repairs. Ended up replacing the spark plugs since I had everything apart and noticed the PO pretty much finger tightened the last set of plugs on. Took the bike into work and it's running fantastic now; much smoother than I remember with no hint of misfire. Seems this may have been my problem after all.
 

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1. get them all out and look at the whole picture rather then individual puzzle pieces
2. make sure these are the correct spark plugs for ur bike
3. they dont have to be torqued (hand tight and then 1/4 turn)
4. dark colors are usually a sign of detonation caused by low octane gas and/or bad gap
5. if u see oil deposits that means oil is getting into the chamber = bad valve guides or rings = misfire/hesitation
6. make sure u dont have a bridged gap this = cylinder not firing
7. ur new spark plugs go bad if ur engine isnt tip top. Ex. #4 +#5
 

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I thought I would update my post with some pictures. You will see the coils and the 2 spark plugs I got out so far.

Also, I have been told that more than likely the oil I am seeing on the plug is not actually oil but something else that just looks like oil. Also odd since the other plug had no sign of that. They both are dark at the tip of the thread though as seen in the pics. These were from coils 2 and 3 by the way.
 

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i thought i would update my post with some pictures. You will see the coils and the 2 spark plugs i got out so far.

Also, i have been told that more than likely the oil i am seeing on the plug is not actually oil but something else that just looks like oil. Also odd since the other plug had no sign of that. They both are dark at the tip of the thread though as seen in the pics. These were from coils 2 and 3 by the way.
pics:
 

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My R6 eats you.
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I've been having the same issues - tore the bike apart yesterday, pulled plug #3 & its totally fried. Just waiting on new plugs to arrive then I'm going to change all 4 (the joy of living in a small town, NAPA didnt have plugs in stock) Hopefully replacing the plugs fixes it...

Talked to Yamaha yesterday - they told me there was no recall on my bike (2003) the only thing he mentioned was that the fuel tank breather/overflow have a tendency to kink which can cause problems.

As I was typing this, NAPA called - plugs are here :) Will update when I know!
 

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My R6 eats you.
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4 new plugs in... Turned they key, hit the ignition and she jumped to life. Throttle is snappy again.... Everything seems great!

One of the coils seemed to have a bit of black shit on it... Like something was burnt but the other 3 looked brand new. So I'll likely replace that one as soon as I can get one.
 

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"The Dude abides .. "
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4 new plugs in... Turned they key, hit the ignition and she jumped to life. Throttle is snappy again.... Everything seems great!

One of the coils seemed to have a bit of black shit on it... Like something was burnt but the other 3 looked brand new. So I'll likely replace that one as soon as I can get one.
have you checked the resistance with a multi meter? manual will show spec range of resistance and how to check (primary is the two leads at top, secondary resistance is putting one in bottom and one on top), or if all the same should be ok. could the black stuff just be oil that leaked past the valve cover gasket into the plug/coil cavity? burnt would obviously be bad (arcing to the engine), but a resistance check should show if that is what it is. more photos :)
 

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burnt would obviously be bad (arcing to the engine), but a resistance check should show if that is what it is. more photos :)
not always true, a coil can show good resistance but if the plastic housing is damaged or burnt providing for a shorter path of less resistance than the spark plug it will just arc to the side resulting in no combustion
 

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"The Dude abides .. "
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not always true, a coil can show good resistance but if the plastic housing is damaged or burnt providing for a shorter path of less resistance than the spark plug it will just arc to the side resulting in no combustion
gotcha. good to know. Still worth a resistance check?
 

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u should have taken closer pics of the tips, but from what i see plugs look fine. where are the other 2?

as far as the coils, again its kinda hard to tell from pic but
check the 2 coils marked with #1 (dark lines going upward from the seam)
check #2 ( spot looks darker and more textured than the other marks)
pull off sleeves marked #3 and inspect the tip of coil
 

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"The Dude abides .. "
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u should have taken closer pics of the tips, but from what i see plugs look fine. where are the other 2?

as far as the coils, again its kinda hard to tell from pic but
check the 2 coils marked with #1 (dark lines going upward from the seam)
check #2 ( spot looks darker and more textured than the other marks)
pull off sleeves marked #3 and inspect the tip of coil
now that i zoom in more i see the spots, from the tumbnail i didn't see that. For literally a "band aid" fix, i have seen these wrapped in electrical tape. Hardly a permanent fix, but will get you buy till ya locate more.
 
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