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Discussion Starter · #1 ·
Hello there,
slowly i don't have any clue anymore.

My 2003 R6 starts stuttering / hesitating at about 2k rpm and again at 2750 rpm after it's running for a few minutes.
It feels and sounds just like a pit lane limiter for a varying period of time and then starts accelerating normal until it hit's the limiter.

I checked the exhaust mainfold temperatures and on cylinder (the rightmost) is about the half of the temperature colder than the others during warm up.

For the beginning in replaced all four spark plugs and the ignition coil on the fourth cylinder. Unfortunately it didn't fix the issue.

Then i got the hint that it could have something to do with false air so i disassembled the whole inlet system and replaced the rubbers between the throttle box and the engine as they were worn out and cracked, cleaned the injectors and while i was working on it, i also checked the gas filter and cleaned the air filter. This made the bike run smoother than before, but didn't fix the issue.

The next step was to check the TPS, unfortunately this also didn't fix the issue but interestingly, the stuttering got less while driving without the TPS sensor plugged in.

The exhaust gases also have a petrol / burnt smell.

I uploaded a video on YouTube with the issue (TPS Sensor plugged in): Video.

As i'm running out of approaches what it could be i want to ask if somebody else already hat that issue and perhaps could help me on that?
 

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Coils are more likely to have issue either at low-RPM with high engine load, --or-- at high-RPM regardless of engine load.
Test your coils with a spark gap tester.
Fire each one to find out what the maximum tolerable gap is; that is, the maximum gap at which it begins to fire inconsistently.
Your outlier is the bad coil.
Also when they do fail, they tend to fail within 10k or so of one-another.
You should be able to produce the same test result, regardless of which wire it's attache to.
 

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Hello there,
slowly i don't have any clue anymore.

My 2003 R6 starts stuttering / hesitating at about 2k rpm and again at 2750 rpm after it's running for a few minutes.
It feels and sounds just like a pit lane limiter for a varying period of time and then starts accelerating normal until it hit's the limiter.

I checked the exhaust mainfold temperatures and on cylinder (the rightmost) is about the half of the temperature colder than the others during warm up.

For the beginning in replaced all four spark plugs and the ignition coil on the fourth cylinder. Unfortunately it didn't fix the issue.

Then i got the hint that it could have something to do with false air so i disassembled the whole inlet system and replaced the rubbers between the throttle box and the engine as they were worn out and cracked, cleaned the injectors and while i was working on it, i also checked the gas filter and cleaned the air filter. This made the bike run smoother than before, but didn't fix the issue.

The next step was to check the TPS, unfortunately this also didn't fix the issue but interestingly, the stuttering got less while driving without the TPS sensor plugged in.

The exhaust gases also have a petrol / burnt smell.

I uploaded a video on YouTube with the issue (TPS Sensor plugged in): Video.

As i'm running out of approaches what it could be i want to ask if somebody else already hat that issue and perhaps could help me on that?
I have a 2004 r6 and I have had these same issues and now it has lost power at the top end and backfires pretty frequently.
 

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UR B-hind Da 8 Ball
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Hello there,
slowly i don't have any clue anymore.

My 2003 R6 starts stuttering / hesitating at about 2k rpm and again at 2750 rpm after it's running for a few minutes.
It feels and sounds just like a pit lane limiter for a varying period of time and then starts accelerating normal until it hit's the limiter.

I checked the exhaust mainfold temperatures and on cylinder (the rightmost) is about the half of the temperature colder than the others during warm up.

For the beginning in replaced all four spark plugs and the ignition coil on the fourth cylinder. Unfortunately it didn't fix the issue.

Then i got the hint that it could have something to do with false air so i disassembled the whole inlet system and replaced the rubbers between the throttle box and the engine as they were worn out and cracked, cleaned the injectors and while i was working on it, i also checked the gas filter and cleaned the air filter. This made the bike run smoother than before, but didn't fix the issue.

The next step was to check the TPS, unfortunately this also didn't fix the issue but interestingly, the stuttering got less while driving without the TPS sensor plugged in.

The exhaust gases also have a petrol / burnt smell.

I uploaded a video on YouTube with the issue (TPS Sensor plugged in): Video.

As i'm running out of approaches what it could be i want to ask if somebody else already hat that issue and perhaps could help me on that?
Swap the #4 coil with one of the others and see if the manifold temperature issue follows the coil. That will determine the coil is the issue. If not, the issue is something else... like the leaky boot, or possibly a valve clearance issue (depending on how many mileskms are on the bike)


Coils are more likely to have issue either at low-RPM with high engine load, --or-- at high-RPM regardless of engine load.
Test your coils with a spark gap tester.
Fire each one to find out what the maximum tolerable gap is; that is, the maximum gap at which it begins to fire inconsistently.
Your outlier is the bad coil.
Also when they do fail, they tend to fail within 10k or so of one-another.
You should be able to produce the same test result, regardless of which wire it's attache to.
Unfortunately, gap testing won’t diagnose the majority of the coil failures. They will test just fine unless the coil pack is in the head where it can arc to ground. The typical failure is a breakdown in the insulation, not a coil winding failure.
 

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Swap the #4 coil with one of the others and see if the manifold temperature issue follows the coil. That will determine the coil is the issue. If not, the issue is something else... like the leaky boot, or possibly a valve clearance issue (depending on how many mileskms are on the bike)



Unfortunately, gap testing won’t diagnose the majority of the coil failures. They will test just fine unless the coil pack is in the head where it can arc to ground. The typical failure is a breakdown in the insulation, not a coil winding failure.
It does have 33k miles but the valve clearance should be good because I had it done this last spring and it started out fine. And I am kinda mechanical and know what's being talked about I just don't have too much experience doing things yet, so I know probably a dumb question but where do I find the coils?
 

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UR B-hind Da 8 Ball
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It does have 33k miles but the valve clearance should be good because I had it done this last spring and it started out fine. And I am kinda mechanical and know what's being talked about I just don't have too much experience doing things yet, so I know probably a dumb question but where do I find the coils?
The coils are the spark plug boots. These bikes have a coil on plug design ignition system. Just unplug the wires and swap the coils on the spark plugs. Then recheck your exhaust temp. Also, make sure the coils are all the way on the spark plugs. They are a bit of a pain, and can sometimes not be fully seated. That can also cause the issue you are describing.
 

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The coils are the spark plug boots. These bikes have a coil on plug design ignition system. Just unplug the wires and swap the coils on the spark plugs. Then recheck your exhaust temp. Also, make sure the coils are all the way on the spark plugs. They are a bit of a pain, and can sometimes not be fully seated. That can also cause the issue you are describing.
Thank you very much, that will be my next step because I don't know how long the spark plugs last but they were replaced like 2 years ago and I only started rising all the time this year. I also checked my tps diagnostic and I can't find what is normal for an 04 r6 but mine is 16 - 97 so that seems normal for other years. This issue seems to be a big one for the 03-05' years.
 

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Unfortunately, gap testing won’t diagnose the majority of the coil failures. They will test just fine unless the coil pack is in the head where it can arc to ground. The typical failure is a breakdown in the insulation, not a coil winding failure.
Wrap it in aluminum foil. Use an alligator clip to ground the foil. It does require a gap tester that can produce a L A R G E gap because both healthy and unhealthy coils will fire at H U G E gaps. Your outlier is the culprit.
 

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Wrap it in aluminum foil. Use an alligator clip to ground the foil. It does require a gap tester that can produce a L A R G E gap because both healthy and unhealthy coils will fire at H U G E gaps. Your outlier is the culprit.
Thank you Intuit I actually just ordered an ignition set that comes with a gap tester. Any Recommendations for coils and line's?
 

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Compare your OEM coils to your replacements. If your OEM have significantly lower resistances for the primary and secondary windings, you'll have to re-gap your copper plugs more frequently. The first batch I purchased were a match, but any of the subsequent ones I bought are not; the lower resistance coils aren't produce anymore. I've looked and looked and looked and haven't been able to locate any that have low resistances like my OEM coils. The manual will list the resistance spec for your CDI / ECU
 

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Discussion Starter · #11 ·
Wow, thanks for all your replies!

Unfortunately i just got a notification for the first one.

I went and got one of those spark gap testers.

It seems like the first one (which i already replaced) almost makes the complete gap.
All of the others are around 1,5 cm, also the one i already replaced.

All of them start to spark within the insulation at some gap.
Is this behaviour normal?

377280
 

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How the hell did you capture that? Step-frame on a video? No, that hasn't been my experience. At max tolerable gap for me, there was either a misfire or spark through the gap. The max gap is the gap at-which it fires with 100% consistency. That boot on the end, is removable. Just because I'm a curious fellow, I'd wonder whether dielectric grease and/or electrical tape would help. But that's not a solution because they would have the coil retain additional heat.
 
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