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2009 Buell XB12SCG, Runs rough when warm

Buellxb Forum

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There is no 'ground' in the ignition coil. Running a battery (-) to the coil mounting bolt is literally putting a wire on plastic, any improvement perceived is psychosomatic.🍄
Yes, a coil can fail with heat (rarely), but more commonly the CPS.
 
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Ok, so here an update.
The CLT measures correct resistance for the temperature. We have also watched the CLT in the log file and it slowly rises as the bike continues to run.
The Leak down test showed no leaks, the cylinders are both making roughly 170psi.
Put a ground from the ground of the battery to the frame and to the engine, no change.
I would love to test the coil with another but we do not have another coil to swap.

I took the bike on a test ride, it rode ok for a while, it did not love a lower/medium throttle so I kept the rpm closer to 4k. When I really got on the throttle I could feel the bike slow down, if I backed off the throttle a little bit, it would begin to accelerate and run better. Further down the test ride the bike began to die on me. I could keep the bike alive and limp it along, the more load that was put on the engine, the more it would die. It finally died on me, I pulled over and started the bike, it would idle ok, take throttle well, when I put it into gear and began to go, the bike would die. Started the bike a couple more times but anytime I tried to get it to move forward, it would die unless I pulled in the clutch and removed the load. I can attach another log file from the buelltooth if that would be of any help to anyone for diagnostic purposes. Also if anyone knows of where I can find a definition of what all the PIDs(AFV,EGO,FLAGS, etc.) mean in the ECMdroid/MegalogViewer that would be very much appreciated, I have searched but cannot find them.
Once again thank you all for your help.

EDIT: Also, I hate to ask this but is there a test procedure or a live data pid for the Crank position sensor(CPS)?
@Cooter
 
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The coil pack is actually TWO coils. Instead of getting the whole motorcycle hot, hit it with a heat gun and see if you can duplicate the problem while the entire rest of the motorcycle is cold.

Same ^^^ old skool test procedure for the CPS.

Ive only read the last couple posts (sorry), but a bad coil/CPS would have some popping and banging when it decides to fire after not firing because the cylinders already saturated with gas. Without popping/banging, it sounds like a fuel volume issue. Clogged sock, clogged filter, or these like to bust the fuel pump output line inside the tank and 'self-return'. It can show 49psi but lack the fuel flow to run well under a load more than just free revving it.

It's a pain to pull it and test it in a bucket (plug the output), but if you have 7 minutes to kill... https://www.buellxb.com/threads/buell-xb-fuel-pump-removal-in-7-minutes.57729/#post-638310

When I get a chance to read the whole thread, I'll edit this as necessary.

Edit: Your TPS at idle reading shouldn't change once set. 'set at 4, goes to 8 when issue"?
IDS is a great company, but an ECM that passed their "test procedure" had me scratching my head before (bad internal fuel pump relay DDFI-2). YMMV. I have several DDFI3 ECM's if you want to try one.
 
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Hello all
Don't know if this helps, if it was mentioned already, please forgive me.
I had a similar issue and it was caused by the Lambda sensor. I changed the original one for a Bosch lambda sensor and this has a feature that it heat up when cold (this was what I understood from the mechaics speech) and when the heating stopped, the values were completly off and caused the engine to stall.
Hope this can help you.
 
Hi. Check the mass of the ECU, you need to remove the muzzle and strengthen the mass on the connector. It's a disease. They are cold because of incorrect voltage, they incorrectly count the temperature, and then it goes off the scale altogether.
 
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According to the values, I don't remember where the document is. Dial the help for ecm. afv mixture, ego lambda probe (exhaust gases)
 
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Hi. Check the mass of the ECU, you need to remove the muzzle and strengthen the mass on the connector. It's a disease. They are cold because of incorrect voltage, they incorrectly count the temperature, and then it goes off the scale altogether.
Yes. Remove muzzle and strengthen mass to help prevent disease🎄🎄
 
The coil pack is actually TWO coils. Instead of getting the whole motorcycle hot, hit it with a heat gun and see if you can duplicate the problem while the entire rest of the motorcycle is cold.
...
The bike was popping during the entire ride out while giving it throttle of the exhaust and then when I had to start limping it along it would also sometimes fire out of the intake. Also in a certain throttle position the bike would surge/lurch, if i twisted the throttle more or less it would smooth out. I will be addressing all of your points next week and posting my findings. Thank you for the ECM lend offer, might be taking you up on it. :)

Hi, did you took into consideration and checked for a broken throttle shaft or a faulty tps sensor ?
We have tested the TPS previously and found no issues but are going to check again. No issues seen with a cracked throttle body shaft.

Hello all
Don't know if this helps, if it was mentioned already, please forgive me.
I had a similar issue and it was caused by the Lambda sensor. I changed the original one for a Bosch lambda sensor and this has a feature that it heat up when cold (this was what I understood from the mechaics speech) and when the heating stopped, the values were completly off and caused the engine to stall.
Hope this can help you.
We have swapped the 02 Sensor with a known good sensor and monitor is values, nothing out of the normal noticed. When it smells rich, the 02 sensor reads rich through the ECMDroid.

Hi. Check the mass of the ECU, you need to remove the muzzle and strengthen the mass on the connector. It's a disease. They are cold because of incorrect voltage, they incorrectly count the temperature, and then it goes off the scale altogether.
Im assuming you are referring to a MAF sensor (Mass air flow). As far as i am aware, this bike only has an IAT sensor (intake air temperature). Please let me know if this is what your referring to or if I am way off base lol.

Thank you all for the help once again, I will be posting more information on the bike and what we find next week. I really do appreciate everyone's help and am looking forward to this thing being fixed. I will be posting more findings next week when I get back to the bike.

EDIT:Screenshot aded, this is from the bike being started and idling for a short time, you can see aroun the blue timing mark where the 02 sensor begins to jump around.
 

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When the o2 Sensor starts to jump around that means it begins to work. And this depends on the value Min Engine Temp in the ECM parameters under o2 Setup. This value has to be 130 degrees Celsius. In your Screenshot the value is 163 degrees Fahrenheit that is 71 degrees Celsius this is much to low and has to be changed.1000024340.jpg
 
The bike was popping during the entire ride out while giving it throttle of the exhaust and then when I had to start limping it along it would also sometimes fire out of the intake. Also in a certain throttle position the bike would surge/lurch, if i twisted the throttle more or less it would smooth out. I will be addressing all of your points next week and posting my findings. Thank you for the ECM lend offer, might be taking you up on it. :)


We have tested the TPS previously and found no issues but are going to check again. No issues seen with a cracked throttle body shaft.


We have swapped the 02 Sensor with a known good sensor and monitor is values, nothing out of the normal noticed. When it smells rich, the 02 sensor reads rich through the ECMDroid.


Im assuming you are referring to a MAF sensor (Mass air flow). As far as i am aware, this bike only has an IAT sensor (intake air temperature). Please let me know if this is what your referring to or if I am way off base lol.

Thank you all for the help once again, I will be posting more information on the bike and what we find next week. I really do appreciate everyone's help and am looking forward to this thing being fixed. I will be posting more findings next week when I get back to the bike.

EDIT:Screenshot aded, this is from the bike being started and idling for a short time, you can see aroun the blue timing mark where the 02 sensor begins to jump around.
The bike was popping during the entire ride out while giving it throttle of the exhaust and then when I had to start limping it along it would also sometimes fire out of the intake. Also in a certain throttle position the bike would surge/lurch, if i twisted the throttle more or less it would smooth out. I will be addressing all of your points next week and posting my findings. Thank you for the ECM lend offer, might be taking you up on it. :)


We have tested the TPS previously and found no issues but are going to check again. No issues seen with a cracked throttle body shaft.


We have swapped the 02 Sensor with a known good sensor and monitor is values, nothing out of the normal noticed. When it smells rich, the 02 sensor reads rich through the ECMDroid.


Im assuming you are referring to a MAF sensor (Mass air flow). As far as i am aware, this bike only has an IAT sensor (intake air temperature). Please let me know if this is what your referring to or if I am way off base lol.

Thank you all for the help once again, I will be posting more information on the bike and what we find next week. I really do appreciate everyone's help and am looking forward to this thing being fixed. I will be posting more findings next week when I get back to the bike.

EDIT:Screenshot aded, this is from the bike being started and idling for a short time, you can see aroun the blue timing mark where the 02 sensor begins to jump aroun
No. No sensors. only the mass in the control unit and the grounding of the battery.
 
The bike was popping during the entire ride out while giving it throttle of the exhaust and then when I had to start limping it along it would also sometimes fire out of the intake. Also in a certain throttle position the bike would surge/lurch, if i twisted the throttle more or less it would smooth out. I will be addressing all of your points next week and posting my findings. Thank you for the ECM lend offer, might be taking you up on it. :)


We have tested the TPS previously and found no issues but are going to check again. No issues seen with a cracked throttle body shaft.


We have swapped the 02 Sensor with a known good sensor and monitor is values, nothing out of the normal noticed. When it smells rich, the 02 sensor reads rich through the ECMDroid.


Im assuming you are referring to a MAF sensor (Mass air flow). As far as i am aware, this bike only has an IAT sensor (intake air temperature). Please let me know if this is what your referring to or if I am way off base lol.

Thank you all for the help once again, I will be posting more information on the bike and what we find next week. I really do appreciate everyone's help and am looking forward to this thing being fixed. I will be posting more findings next week when I get back to the bike.

EDIT:Screenshot aded, this is from the bike being started and idling for a short time, you can see aroun the blue timing mark where the 02 sensor begins to jump around.
Also reset the afv
I don't speak English, it may be difficult to translate.
 
There is no 'ground' in the ignition coil. Running a battery (-) to the coil mounting bolt is literally putting a wire on plastic, any improvement perceived is psychosomatic.🍄
Yes, a coil can fail with heat (rarely), but more commonly the CPS.
"Grounding the ignition coil" is actually grounding the ignition coil mount. And the mount is firmly connected to the engine.
Grounding the engine on the ignition coil mount, would be a better description.
 
Reading the complete thread makes me suspect the TPS (Throttle Position Sensor) and here is why:
You wrote on TPS: "It sits at around 4 at idle, when it begins to run rich/rough this will change closer to 8"
It is vise versa: When Throttle Position changes, the result is that the engine runs different.
Throttle Position Sensor data is supposed to be related 1:1 with the position of the throttle handle.
Does the TPS change value by itself?

Looking at the picture of the log makes me wonder too; why is the TPS Voltage irradicate?
No stable idle, could make you correcting the Thottle Position value to keep the engine going but otherwise ...the TPS is faulty.
With no hand on the throttle handle, the Throttle Position value is not supposed to change.

Could be the grounding of the TPS too (i.e. ECM grounding).
 
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This might be a long shot, but I had a similar issue with the bike running rough and back firing.
Tried all sorts of things and in the end found a post about the grounding issues on our bikes,
added some new grounding to the engine mount under the airbox cover and the ignition coil directly from the battery and all my issues went away.
There are quite a few posts on various Buell forums about this.
Costs more or less nothing so no loss if it doesn't help ;)
Same
 
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