I'm a real loner and have always been a do-it-my-self without help guy - But, I assure you Mr, H - I would gladly take the help if you were here!

I agree completely with what you are saying, and absolutely understand what you are saying.

As for your discussion on injectors, I do recall reading that discussion and using the info, and I replaced mine with the white band injectors to see if there was any change in the running, and there was no change. This was back when it was just the occasional chuff on first cold start up. I figured it was a cold lean burn condition and the new injectors might correct that, which it did not.
At that time, all the fuel rail and O-rings were inspected and actually quite impressed as there was not a one that was not soft and have zero flattening on them. I commented on what I found somewhere in the threads. It was impressive to see O-rings that looked to be virtually brand new in a fuel system.

So, my end results of the fuel system:
Strong pressure, checked solid fuel flow, all fittings O-rings good. No leak down of the system when pressured. 58 psi while running. The OEM fuel pump appears to be working as it should, and the OEM pressure regulator is also appearing to be functioning correctly. I could put the original injectors back in, but I am very confident that it would show the exact same running condition.
Air intake has been examined numerous times. The IAC operates just as described in the book and has been cleaned. Filter is close to new, intake is all clean. Gaskets checked, leak check found no vacuum leaks. Throttle positions sensor actuator was off and put back on exactly as described, and as the book states - No adjustment required.

I am going to sit down and go through the troubleshooting of each of the components I have in that list above and see what checks I can do on each.
I have air, fuel, spark. It runs, but there is a definite chuff in the intake, with or without the air filter installed. There is also a misfire in the exhaust. It gets worse after running the bike and shutting down and allowing heat soakback.

Now, when I made it home two Fridays ago it was running horribly. At this point, it is running far better - Why that has me baffled. Did I have multiple things going on that day, and I have corrected some of it by the new plug wires ? The new coil [ could have been a used one ] did not change a thing, and both ohm checks fine statically. New plugs made no difference. CPK no difference. So why is it running a little better and almost seems to be back to the condition of the horrible running, but still not right?

So somewhere I have touched on something that did "help" the condition. That is what is making it so hard.

I had high hopes the 2.65V reading of the CPK was it, the new CPK is now putting out 4.65V - but evidently the 2.65V was enough, and the new sensor has made no change in running.

Go forward plan. Read the books on the way to check, if there is a way to check, the MAP, IAT, sensors. The chuff in the intake is obviously a back blow of firing at either the incorrect time or the incorrect amount of something.

As for compression, the bike has a ton, and will blow your hat or hair straight up, when doing cranks to check the CPK readings.

I also hate "throwing" parts at it. I also agree and have been, believe me, trying to troubleshoot this at an old school standpoint. But, all the items that would have been the old school approach, Coil, plugs, wires, ect... have been replaced. The one way I try and tell myself it's ok, is that the bike is 23 years old and if it is not the problem fixer, maybe I am doing preventive parts replacement pre-failure. And, I have spares for a bike or a similar bike in the future. It makes buying the parts a little less painful.
But, yes, I hate throwing parts at a problem, and it is not my normal method in any manner.
I'm just lost here and stumped, which rarely happens to me when fixing things. I fact, I have never been stumped like this before, at my work or my personal things that break.

For me, the big clues have been ;
Condition has come on slowly over a long period of time and finally got a lot worse.
Seemed to have had an actual failure on that last ride. Something gave out.
Better after plug wires were changed with some I made out of braided steel core leads.
Chuff out the intake pretty quickly after start-up and even while the first start attempt.
The Misfire in the exhaust at mid rpm, steady throttle.

It's trying to tell me what is wrong, I'm just too stupid to know what it's saying...

Thank you Mr. H !!! You help keep me grounded. I appreciate any and all advice.

 

Braided steel core plug wires:
I would be careful about adding non-OEM spec parts when looking for a hard to find problem.

The ION-Sensing system in the Twin Cam's Delphi EFI system detects and adjusts for spark knock. There have been documented cases of certain plugs, and plug wires that don't play well with the Ion-sensig. If the resistance doesn't match OEM spec, it can trigger the Ion sensing to retard timing, thinking there is detonation, and cause poor running.

I'm not sure what plug wires you used, or how they compare to OEM, but I would stick with OEM spec stuff until I found the cause of this issue.

The "chuff" out the intake:
Is that like a backfire out the intake? A backfire through the intake on EFI is usually a miss fire or timing issue. I'd be using some inline spark plug testers to try and see which plug, and how often the spark is misfiring

Also, IIRC, you earlier mentioned removing a piggy back tuner, then having the ECU flashed back to OEM. Why the reflash after removing a piggy back tuner? I forget... what mods do you have?

 

I bought and installed the OEM wires yesterday. The steel core leads were for troubleshooting shooting and the bike ran better after that was done. But, they are out of the equation now with the new set of OEM wires.
Yes, it had that piggy and was removed to see if that was the issue way back. Reflash was your recommendation after it's removal because you said that it can mess with the OEM ECM. I had the shop do a fresh flash back to factory specs. Bike is 100% OEM. The one and only thing that is not completely as it came from the factory is that the breather lines are now routed to the atmosphere.

Yes, I agree completely - the chuff in the intake is a sign, and that is where it all started. Yet, no misfire codes? That is also why I sprung for the CPK, thinking that the low 2.6V might be causing that. It's not.

The more I think about it 24/7 and even in my sleep.... The MAP sensor could be the issue ????

Here is a funny, not really funny, as it shows how long I have been F'in with this... Little over two years ago, I was on Jury Duty. Guess what was in my backpack I took for reading material? Yep, the HD factory manuals and guides - good time to read up on all the things that can cause this odd chuff and occasional kick. Yeah, it kicked - kicked my ***. The funny part is I am on Jury Duty through May, guess what books I have with me in the backpack....

So funny, I feel like killing myself.

 

Marlinspike, I have read through this thread and I see all the components you have checked and tested... I had similar issue and it turned out to be very bad spark plugs... I see yours look great and only 1k miles on them... Have you checked for water in the fuel tank? I may have missed that in the posts but I don't recall seeing you checking for that. I would suggest draining the tank all the way and see if there is any in the fuel. Could have picked some up fueling up, or just the air in the tank condensing on a cool night and cause water in the fuel, and over time this can create a problem with bike running rough and missing... Just a thought.

 

If you got that info from me, than I apologize for not being clear.... or saying soemthing wrong to leave the impression that the OEM ECM needs to be re-flashed if you suspect a bad piggyback tuner.

I don't believe piggyback tuners will change the tune in the ECM. They change the signals from the ECM to the injectors, but only when they are attached...

I usually recommend removing them, to see what happens with them out of the loop, not also reflashing the ECM... I suppose they could corrupt the software in the ECM, but I don't recall ever hearing of that issue with piggyback tuners.

The only time I suggest re-flashing the ECM is when there is an issue with a flashed/downloaded tune... And I will usually recommend another tune altogether.. or to check components of the tune (ie: what is enabled and/or disabled in the current tune).

Anyways, I'm anxiously awaiting the fix for this issue.

PS-
I too do all my own work now. I have for the last 15 years. My Bro in-law is retired, but used to be a Service Writer for a large Kansas City Harley dealership. I will consult him from time to time, but I've yet to need him to dive the hour between us, to help me on one of my bikes... yet...

My point is sometimes, it's a good thing to get a fresh set of eyes on an issue, especially if you know a knowledgeable person. While there are several on this site that offer ideas, it's totally different when you actually can go hands on, to inspect & check things on your own...

Barring a knowledgeable friend, I have almost taken my bike to a trusted Indy to get his opinion a couple times. Luckily I had a breakthrough just prior to putting the bike on a trailer...

There's no shame in paying a few hours labor for a second, qualified opinion... just a thought...

 

First to answer Mr. W.
I tried a brand new set of plugs. Same condition. As for the fuel, it is fresh fuel and yes, that is almost exactly what it "use" to feel like when it would do a Kick or burp way back when this first started. Just a complete stop and start while riding - just like a gulp of water. That Kick or burp started turning into a chuff in the intake, which then, three weeks ago, added a solid misfire.
I drained all the fuel and started over fresh just a month and a half ago. If there was any water or condensation, I would have thought it would have burned through while struggling to get home from Custer Park. But yes, I did give that thought.

Mr H, I believe I asked you about the tuner I had, and you said something along those lines of not liking those piggy types because they can mess with the ECM. I probably misunderstood, and after removing it from the bike, and still have running chuffs and occasional kicks, I figured a fresh update might straighten things out - It did not. The HD tech said something along the same lines as the Piggy can mess things up. While doing that, he said there were no codes logged currently or in history. Just like right now. That is another item that baffles me and points me towards what Mr. W said about water or some kind of issue that is not a true misfire or electrical breakdown item.
But like all the things I have done, little attempts to get to whatever is going on. Then it got bad, and here I am. Thus damn thing started a long time ago and has finally develeoped to a real issue - like barley made it home issue. The only thing that seems to have had any impact on the horrible running condition is the plug wires - that has to be a clue.
Could it still be a coil ? I checked the original, ohms good, tried what I was told was a NOS OEM, ohmed good, but yet both have the same running condition. 2 bad coils ???

As for taking it to a shop. The HD dealer is the only shop I know of. I have never had any interaction or heard of anyone recommending an indy shop.

I will sit down with the troubleshooting book, sit and really read it, and follow the processes closely. I have, but not sit and solidly read it. More like I scan to the area of what it is that I want to troubleshoot and do that procedure if it does not require the scanilizer tool. I was not able to get to it today. I take care of everything at my moms place, and she keeps me plenty busy. She's 100 1/2.

Gut feeling from the start a couple of years ago, when this was only occasionally happening. Water in the fuel, then the Piggy unit, then something in the fuel system that was aged, then coil or CPK, then wires as this became much worse.

Guys - I truly appreciate you trying to help me out. If in any way I respond to a comment or something I say that gives you the feeling I am not taking your advice - That is absolutely not the case. I am and will take every single thing mentioned into the equation and try to see if there is any possibility that is what is going on.

So, Thank you !

 

Well, I know better than to say, "No way." Stranger things have happened.... BUT... they both test good. I would look elsewhere.... for now..

The only thing I don't recall you testing is the ECM... The ECM tells the coil when to fire, based on the timing from the CKP. The ECM controls the Ion sensing adjustments. The ECM is takes input from several sensors you've checked, to make the bike run.

At this point, I would check the ECM, however the manual says to do it... If the ECM passes muster, time to consider other possibilities.

If the ECM checks OK, here's what I would do...

You have had the issue morph over time. You have had some things affect the running only to have it go bad again...

Many of your checks have been over a time period also... so...

If the ECM checks OK, I would start all over, go A to B, one at a time, and check everything. I wouldn't think, "I checked that 6 months ago, it was good." I would everything in immediate succession, with minimal time between A to Z.... and record (write down) all tests with results.


Compression:
I'd do both a compression check, and a leak-down test.

All good?.....check

Air:
I would check over the air filter, intake manifold seals, induction module o-ring to manifold, anything that is plugged into the manifold for possible leaks, and IAC.

All good?.....check

Fuel:
I would run another pressure test on the tank fitting to confirm the tank internals are still working properly. I would also do a good visual inside the tank to rule out any tank liner peeling and causing intermittent fuel starvation. Then I would remove and inspect the fuel line, fuel rail, and revisit an inspection of the Fuel Injectors (you did use HD injectors?)

All good?.....check

Spark:
Electrical is my least favorite and the one you need to be the most persistent, thorough, and systematic while checking.

If that all doesn't find an issue, then it is time to get a second set of eyes on it. It's often hard to check your own work, just like it's always better to have someone else proof read your paper...



On one issue in the not too recent past, I checked for codes:
Bike showed none.
My PowerVision tuner showed none.
My Techno-Research Centurion Pro showed two codes, which led me straight to my issue.. Go figure..
I am lucky to have acquired a lot of tools over the years. Especially since I have been retired, and working on my bikes is my past time.

However you choose attack this, keep us posted.. I have no doubt you have the skills to solve this, and I am very curious as to the outcome.

 

Engine Temperature Sensor maybe? Mine went bad and the bike ran like crap when warmed up but I've read where they can cause problems at any temperature. Even at start up.

 

If your riding in Custer Park there has to be a couple of good Indy mechanics close that should be able to diagnose this issue. Hate to see you not get the problem resolved and miss out on riding. At some point maybe a different set of eye's and experiences might be in order. Paying to get rid of frustrations is sometimes beneficial. Riding seasons to short in the frozen tundra.

 

Ok - back out to my shop.
Started reading through all the troubleshooting schematics. Funny how easy it is for the arrows o take you to "replace ECM" "Replace XXX" - like it's your money they are spending !

Ok -Since most all lof the items Mr. H listed have been done, and done within the last couple of times the bike was ridden. including draining the fuel and fresh fill of Zero Eth Prem, which is all I have ever used, or anyone here for that matter. I have not and can't really find an easy way to do much with the ECM, and the book writes it off as an item to replace pretty damn easily.

I have had in my mind the MAP sensor. Manifold Air Pressure, sensor for anyone following my drama. Ok - Pulled the connector, volt checks 5V DC just like it is supposed to. That verifies power is getting ot it. Here is the biggie that might be something. Leaving the connector disconnected. Fired the bike up. Took a couple of tries and a chuff from the intake, like it has always done first start since this started. Bike ran exactly like it has been - Zero change with the MAP sensor disconnected, meaning it was not doing anything, and the bike even when rev'd up, was 100% running like it has been running. Not worse, exactly like it has been.

SO - does that indicate to anyone else that the MAP sensor may not be functioning and causing the running and chuffing, and misfire? Sure looks like it to me. A chuff in the Aerospace world is a lean burn at start, and that is exactly what it has been acting like. I think I just might be on to my demon.

I know the seal is good because that was all part of the intake seals inspection just a short time ago.
I could do further volt checks on it while running and have inline wire connections that checks high and low volts and different conditions, but it shows me it is getting the proper volts from the ECM, by what I checked.

So what does the - Think Tank Panel think of what I found?

Bad part. = Looked the MAP sensor up on the HD site - No Longer Available..... I'll cross that later I guess.