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Discussion Starter #1
Hi everyone,

As part of a triple bypass I took off the Turbo and the Exhaust manifold. I discovered that the left side of the manifold (as well as the cylinder outlet) is covered with significantly more carbon than the right side. It seems like the engine is running way reacher on the left-side than on the right.

Now, I don't remember ever seeing any significant difference between the carbon buildup on the spark plugs when I replace them. So I am thinking it is possible that there was once an issue with the bike and the issue got fixed long before I owned it.
On the other hand, it could be a small difference between the side that shows only on long buildups (ie manifold and outlets) and not of spark plugs that gets replaced often.

Questions:
1) Has anyone ever seen such issue (ie the exhaust on one side is dirtier than the other)?
2) Are there efficient ways to measure the quality of the combustion of each cylinder separately?
3) Is there a way to measure the amount of fuel each injector injects while it is running in the engine? (yeah, I can measure the electrical pulse width at the injector, but that doesn't tell me if the injector is clogged or leaking, etc).

Thanks!
 

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Hi everyone,

As part of a triple bypass I took off the Turbo and the Exhaust manifold. I discovered that the left side of the manifold (as well as the cylinder outlet) is covered with significantly more carbon than the right side. It seems like the engine is running way reacher on the left-side than on the right.

Now, I don't remember ever seeing any significant difference between the carbon buildup on the spark plugs when I replace them. So I am thinking it is possible that there was once an issue with the bike and the issue got fixed long before I owned it.
On the other hand, it could be a small difference between the side that shows only on long buildups (ie manifold and outlets) and not of spark plugs that gets replaced often.

Questions:
1) Has anyone ever seen such issue (ie the exhaust on one side is dirtier than the other)?
2) Are there efficient ways to measure the quality of the combustion of each cylinder separately?
3) Is there a way to measure the amount of fuel each injector injects while it is running in the engine? (yeah, I can measure the electrical pulse width at the injector, but that doesn't tell me if the injector is clogged or leaking, etc).

Thanks!
not a turbo expert but owned several fuel injected BMWS- whats available in terms of diagnostics?
injectors been replaced? cleaned?
What fuel is used?
 

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Discussion Starter #3
not a turbo expert but owned several fuel injected BMWS- whats available in terms of diagnostics?
injectors been replaced? cleaned?
What fuel is used?
I haven't replaced anything yet. I do not know what had been replaced before I purchased the bike 5 years ago.
In fact, I do not know if the issue still exists: The engine runs fine, sounds even/balanced at idle, no black smoke, some backfires on long engine-breaking downhills. Furthermore, spark plugs come out relatively clean on both sides. This is the first time I take off the exhaust manifold, and only there I see a significant amount of carbon on once side only...
So I am not sure if there is a problem at all.. but still, wanted to be able to verify after I put everything back in place.
I guess that's my question exactly - "what is available in terms of diagnostics?"
 

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I haven't replaced anything yet. I do not know what had been replaced before I purchased the bike 5 years ago.
In fact, I do not know if the issue still exists: The engine runs fine, sounds even/balanced at idle, no black smoke, some backfires on long engine-breaking downhills. Furthermore, spark plugs come out relatively clean on both sides. This is the first time I take off the exhaust manifold, and only there I see a significant amount of carbon on once side only...
So I am not sure if there is a problem at all.. but still, wanted to be able to verify after I put everything back in place.
I guess that's my question exactly - "what is available in terms of diagnostics?"
I'd have the injectors cleaned and "bench-tested" as the first step-easy to remove and refit;
Many aftermarket diagnostic sets exist e.g.TEXA-but the turbo had a specific service set I believe-other forum members can advise
 

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Discussion Starter #5
I'd have the injectors cleaned and "bench-tested" as the first step-easy to remove and refit;
Many aftermarket diagnostic sets exist e.g.TEXA-but the turbo had a specific service set I believe-other forum members can advise
Thanks!!
 

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Watch this, and replace the coil wire or snip off the corroded ends. This guy has a series of videos that are pretty good, you may want to watch others or the complete series for other ideas.
 

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Discussion Starter #7
Watch this, and replace the coil wire or snip off the corroded ends. This guy has a series of videos that are pretty good, you may want to watch others or the complete series for other ideas.
Very interesting video... and the rest of the days as well.
As for my case - I am not sure if there is still an issue or if the carbon buildup is leftover from an issue that was there before and is already fixed. The engine runs smooth, starts up immediately, no dark smoke out of the pipes, spark plugs seem pretty much carbon free after 5Kmiles. Allegedly, everything is ok. I'm more of looking for a method that prove that that's the case.

On modern FI systems there is an oxygen sensor that could tell if the mixture is reach or lean. We don't have that.
In the old days, mechanics used to use a transparent spark plug (with glass isolation instead of ceramic) and observe the color of the combustion.
Any other methods you guys are aware of?
 

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High Temp Infrared Thermometer Digital IR Temperature Gauge. Its a tried and true method to determine cylinder to cylinder combustion efficiency. Doesn't get any cheaper or easier than this.
 

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Discussion Starter #9
High Temp Infrared Thermometer Digital IR Temperature Gauge. Its a tried and true method to determine cylinder to cylinder combustion efficiency. Doesn't get any cheaper or easier than this.
ahh! that's a good idea. I have a corona IR thermometer. I hope it is accurate enough and can go that high.. perfect!
 
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