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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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