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Moarant
Posted on Saturday, June 24, 2017 - 08:33 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

any advice appreciated. last year bike would loose power on sustained high rpm runs (freeway). codes 13, 15, 21, 36, put bike up for winter. got bike out. new battery, new o2 sensor, new air temp sensor. Tried to start - would not fire front cylinder. took to local HD shop (useless endeavor). Charged me $$$ to change plugs and tell me nothing was wrong. I then replaced the ignition coil and plug wires. Ran fine for 15 minutes then engine light on (when on freeway). Started loosing power and missing again as well. Codes 13 and 21 again.

exhaust valve checks out. cycles and has correct ohm. has a tendency to backfire through throttle body if throttle is "blipped" when coming to a stop.

I am at a loss as to what to look for. has anyone seen this before? Should i be looking for a ground fault? is this a known ECM failure mode? Any advice please.

thanks
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Two_seasons
Posted on Saturday, June 24, 2017 - 11:02 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I don't own your model of bike, but I would check your grounds and your ecm connections.

I assume you have the service manual for your bike?

Please post each code fault name.

We'll get this figured out for sure once we have more info on the codes.
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Moarant
Posted on Sunday, June 25, 2017 - 08:42 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

thanks. trouble codes from before the new parts:
13 Oxygen sensor
15 Intake air temperature sensor (Note this one might be an error - may have left it off when re-assembling a test fire)
16 Battery voltage
21 inter active muffler control
36 fan voltage

After new battery, new air temp sensor, new plugs, new coil, new plug wires, new o2 sensor, I have:

13 Oxygen sensor
21 inter active muffler control

Now for the fun part. even when the bike would not fire on the front cylinder, I never got a code 23 (front injector) or code 24 (front coil). Even with a serious miss now, I only get O2 and exhaust. I suspect O2 is from a really rich or lean issue. But o2 is on rear cylinder which I have not observed misfiring (but this may be an observance issue and it is misfiring like the front as well).

Yes I have a shop manual. But it is on the moving truck. Will not get it back until next Friday. Bike is with me in temporary living.

This has to be some type of ground / short / break / etc. somewhere in the tangle of wires. Or the ECM is just failing. I just bought a buelltooth but have not yet hooked it up. I'll post any interesting info from that once I do.

I was hoping that someone reading this would remember a case like this and know that it was a failing ECM or a harness problem in a particular location. Someway to refine the search on this one.

anyone make a good electron leak detector (: )) to locate the electrical failure?

thanks
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Moarant
Posted on Sunday, June 25, 2017 - 11:05 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

forgot to note: bike has 34,000 miles on it....
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Akbuell
Posted on Sunday, June 25, 2017 - 12:09 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

First wild guess: While tubers are brothers with different mothers, a cascade of trouble codes and an engine miss is often a sign of an engine temp sensor failing or going out of calibration. It can happen without showing a fault code. Been there, done that. Might do to look at the ETS wire for signs of chafing, ect.

Second wild guess: Look carefully at the ECM plugs for signs of cracking, and wear on the harness where it may have been rubbed by the seat pan. Might even try running the engine with the seat off, and wiggle test the harness and plug-ins at the ECM.

After that, it is back to looking for loose battery cables, bad grounds, and so on.

I did have a Lucas electron leak detector, but the batteries in the smoke alarm died . . . .

Anyway, hope this helps, Dave
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Moarant
Posted on Sunday, June 25, 2017 - 08:57 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

thank you Akbuell. Temp sensor is a great idea. given the age of the bike and the miles, I am just going to replace it. I am tiered of guessing and will just brute force through the issue list. just have to wait for my tools to arrive from the move to NC.

I have had rounds with wire rubs / shorts already (behind headlights, harness coming off the ECM, .... I was anticipating a fun filled Saturday removing the wires and inspection....

What kills me is that this only seems to happen at sustained freeway speeds (3,500 rpm). That sounds all the world like a failed exhaust valve. but it passes all the tests. Does anyone think that removing the cable and locking the valve open would be a worth while test? I will loose a bit of mid-range power but I will be sure that I have full exhaust.

thanks for the ideas....
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Gabby_duck
Posted on Tuesday, June 27, 2017 - 11:47 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

1st I would suspect a faulty ecm or (as above engine temp sensor).
2nd fresh gas make sure battery connection are physically tight
Remove seat and airbox cover and filter airbox. Reconnect air temp sensor.Inspect wires running near cyl #1 look for melted wire harness etc. Start bike and do wiggle test on wires. On front injector i had a broken strand under wire insulation.That will look and feel like a hump inside of the insulation.hook up your Bluetooth and download ecmdroid. What specifically is the O2 code also what is your AFV #
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Gabby_duck
Posted on Friday, June 30, 2017 - 03:47 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Reset AFV to 100 after repairs, Adaptive fuel value is learned another name would be long term fuel trim. 100 = 0 on these bikes
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Gabby_duck
Posted on Monday, July 03, 2017 - 04:46 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

P.S absolutely no dielectric grease should be applied to any o2 sensor wire or connectors .
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Moarant
Posted on Wednesday, July 12, 2017 - 06:40 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

thank you all.

Finally moved into new house and have internet.....

During all of this, please remember that the bike has 34,000 miles on it. More than a typical bike.....

It gets even more strange. Thanks akbuell for the temp sensor idea. I changed it (it was the original I believe). But i do not think the old one was bad. So after changing the temp sensor I took it for a ride - no effect. I then started using buelltooth and ecmdroid to run tests. ALL tests passed, but I noticed that the exhaust servo was really slow to actuate. It is the old plastic gear version. So I disconnected the cable and used a fender washer on one of the torx screws to hold the exhaust valve open. Servo could now swing freely (no load on servo). Went for a ride - same general issues and error code 21 (exhaust valve stuck). So i used bulltooth (man I cannot believe that thing was so cheap for what it does) to turn off the exhaust servo altogether. Went for a ride again. Same issues with error code 13 (O2 not responding and then later O2 lean).

Now the O2 is only 6 months old so I do not think it is bad. Also, the symptoms this bike has displayed are not normal for a short:
1) Below 3000 rpm bike runs perfectly (with or without the exhaust working)
2) Sustained running between 3000 and 4000 rpm results in one cylinder deactivating every 2 minutes or so.
3) However, if I roll onto the throttle or cut the throttle, the bike instantly recovers and runs fine.

This is why I was thinking that the issue was the exhaust servo not responding as the "mid range rpm" cruising mode is the only place it misbehaves. But turning the exhaust valve off did not fix the issue.

I have not yet reset the AFV (thank you Gabby) and that might be part of the problem. I plan to do that.


QUESTION 1
Is there any reason to think that simply disabling the exhaust servo and holding the valve open would cause a lean condition? I cannot be messing with air flow rates that much. Should I try keeping the valve closed with the servo deactivated? This is a commuter bike so the small hit in horses is acceptable.

While I cannot guarantee that it is always the front cylinder that is "off", I have been able to reproduce the issue at idle (before I replaced the coil, plugs, wires) and the front cylinder was the non-functioning one. Note: I have only observed this issue out side of the 3000 - 4000 rpm range twice. Once when first starting after 6 months of winter storage. and once a year ago before replacing the O2 sensor.

That leads to QUESTION 2:
When an overheat situation arises (or the ecm thinks there is an over heat issue), which cylinder does the computer shut down? I would have thought it would be the rear cylinder given the lower air flow but do not know.

QUESTION 3
I am willing to replace the injectors if anyone thinks there is a rational reason to do so. But fuel demand cruising at 60 mph (just below the failure rpm point) is not much different that at 70 mph (well into the failure range) and snapping the throttle open results in instant acceleration - even in 5th gear. no lag, no stumble, no strange sounds. Any reason to suspect fuel delivery?

QUESTION 4:
I am willing to work on the harness but this does not seem to act like any short / fault / wire issue I have ever seen before. No fuses, no codes dealing with voltage, no issues cranking / running / lights / etc., only occurs at the 3000 - 4000 rpm range AT PART THROTTLE. Anyone have a different read?

QUESTION 5:
I am strongly thinking that this is a bad ecm issue at the moment but I have no way to prove that (unless there is some other super duper feature hidden in buelltooth that I do not know about). Should I try a race ECM? Regulations here only require tires / lights / horn / etc. And i have the servo deactivated anyway.

Thanks for the advice.
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Moarant
Posted on Sunday, July 22, 2018 - 03:53 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Final solution!

Note to the site admin. You may move / reuse / edit / whatever you like. Figured that this was worth others knowing.

For 3 years I have been fighting the same frustrating issue with this bike. It runs well around town but will randomly start misfiring at interstate speed while cruising. Cutting the throttle OR going to WOT returns the bike to normal mode for a minute or so and then it starts misfiring again. Issue occurs between 3300 and 3700 rpm. I got a lot of good advice from the forums on where to look but this one seems to have stumped everyone.

Well I finally solved this issue and from what I read, there are a bunch of other users with the same general issue that cannot find a resolution. I feel confident that I got the issue fixed this time as I have gone 3 months and 1,000 miles with no issue. So to save others the time and money, here is the history, hypotheses, and fix. It is a bit of a tale but read it so you know what DOES NOT work.

When this started (2016) I would occasionally (not always) get the following codes:
13 Oxygen sensor
15 Intake air temperature sensor
14 Engine temperature sensor
16 Battery voltage
21 inter active muffler control
36 fan voltage

I installed new battery, O2 sensor, air temp sensor in 2016. Bike worked for 1 week then issue returned. Near winter so I parked the bike.

In 2017 I tested the fuel system and it seemed that fuel was being delivered properly so I guessed that the issue was electrical. Installed new plugs, wires, coil. Bike worked for 2 days then back to the same crap.

A few completely useless dealer services resulted in new plugs (again) and a re-flash of the computer (and a lot of $).

Did a complete wiring harness test (puled all the connectors, checked all the wires, checked the computer connections, ….). Found a few small items but nothing that fixed the issue. It occurred to me that the exhaust valve opens and closes at this rpm range and the muffler was rusted (35,000 miles). So I disconnected the exhaust cable and jammed the valve open. Exhaust servo was free to rotate. No effect – same problem. But I could not rule out an issue with the exhaust servo itself.

Contacted KD Fab and got a drummer muffler (NO STUPID VALVES) made and an IDS computer to match. KD was really helpful with good quality work. I knew I had this fixed now with a new muffler, computer and no servo. WRONG. Bike worked great for 2 days and then the misfire issue started all over again. But now the only errors were:

13 Oxygen sensor
15 Intake air temperature sensor
14 Engine temperature sensor

During 2017, I had noticed that my oil level was growing slowly during all of this so I thought that maybe the pressure regulator was pumping gas into the oil and (maybe) not supplying the injectors properly. The bike had 35,000 miles so it was probably due for a pump. It also seemed possible that I had an intake air leak that was vibration dependent or the TPS was shaking at the right frequency. Remember, this only occurred between 3300 and 3700 rpm. So I had a new fuel pump, regulator, throttle body (with new injectors, TPS, and seals), new plugs, and a new o2 installed (KD did the work). The plugs and O2 were in case the misfiring had fouled the last set. Bike worked great for 2 weeks then the same problem again.

At this point I was considering the bike for scrap metal. $2,500+ in parts with no success. That said, all the parts I replaced were worn after so many miles and it was not irrational to replace them. Plus I knew a few were bad (fuel pressure, the first o2, ….). But what could possibly be wrong with this thing?

I went back to electrical (through shear process of elimination!) and thought about the errors, all three were from sensors on the same section of wiring harness. The O2 and engine temp are also single wire (duplexed signal) so any loss in battery voltage / circuit conductivity would cause them to appear failed. I clipped the sensors out of the wiring harness and built a new harness for these sensors that then spliced into the connectors at the computer. The original wires were taped at both ends. I knew I had to have the issue now. I had all new parts and new wiring to the sensors that were throwing codes. Test rode the bike and ….. FAIL!!!! Same issue again.

More thinking and screaming at the bike led me to suspect that there might be a ground issue. I had already checked this multiple times but I did again. No loose grounds. But what if the computer was not grounding well where I could not check? This was obviously a vibration issue where something was shaking. So I figured adding an extra ground would not hurt anything. I spliced into the black wire at the computer terminal (that is the ground wire for the electrical system). I made a connector for the splice and bolted it to the negative battery post. Now the harness was definitely grounded. AMAZINGLY - PROBLEM SOLVED.

It has been 3 months and 1000 miles trouble free. No, the bike has not burned down. No, the bike has not blown fuses. No, the bike has not fried the IDS computer. All seems well. So the hypothesis is that the computer itself is losing grounding when shaking (do not have an explanation for where / how). Now I do not fault the computer as TWO computers have been tried without success before. Remember that I ohm tested all the grounds to the computer while shaking the harness 2 years ago and again this year. I never found a loose ground or a break in the wiring that would affect this (did have to re-wire the head lights as a separate issue). I also added a foam stopper on top of the battery to keep the seat off the computer connectors in 2016. As best I can tell, this is an issue with how the computer is grounded / seated.

If anyone has an alternate hypothesis, please add it. But I can tell you that multiple people have gone through this bike and not found the root cause (including me). Adding a ground to the wiring harness at the terminal (total of $0.12 in materials) solved what $2,500 had not. So, if you are one of the poor souls with a cruising speed misfire that cannot be eradicated, just try adding an additional ground to the computer. It cannot hurt anything.

Side note: I do believe that the stupid exhaust valve and servo (thank you California pass by noise) were an issue. I suspect that some of the codes I was pulling were real servo codes that just happened to pop up during a ride that the ground fault occurred. KD did really good work on my bike so you might want to get a muffler / computer without the stupid valve.

Parts:
O2 sensor 3 replacements
Air temp sensor
Engine temp sensor
Battery 3 replacements
Ignition coil
Plug wires
Pugs 3 sets
Muffler
IDS computer
Throttle body
TPS sensor
Fuel pump
Fuel regulator
Fuel injectors
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John_vreede
Posted on Wednesday, August 22, 2018 - 12:46 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

If you're looking for stuff on earth / earthing / grounds / bonding and cleaning there's another post that bears directly on this with a checklist on what to look for and how to do it:
http://www.badweatherbikers.com/buell/messages/384 2/834493.html?1534482516
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