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Preliminary to a further reply by Max:
1. The ECM has an internal 5 vdc poower supply for sensors. The black/yellow output is going to be less with engine off for two reasons:
a. With key on, but engine not running, there is electrical drain, especially from the headlight, sagging the voltage.
b. With engine running, the 3 phase alternator is recharging the battery at 13.8 to 14.8 volts.
2. I am remain concerned about a vacuum leak, such as the two vacuum hose fittings or a poor electrical connection. However, a poor connection should result in a DTC:
12-1 for fuel injector 1
13-1 for fuel injector 2
14-1 for fuel injector 3
15-1 for fuel injector 4
29-1 for IACV, etc.
3. The earlier suggestion about the evap canister purge is worth considering. Max may have a different approach, but I would be inclined to unplug the "evap purge control solenoid valve". Wires are bl/w to junction and bl/y to ECM A29. That position is labeled PCS on the factory schematics. No clue as to when the ECM triggers a purge (definitely engine running and full operating temperature, maybe minimum RPM?), but be interesting to take that out of the picture. This thread has a clue as to its location (easily seen in front of airbox from right side-easy to unplug electrical connection) and another clue for this saga: http://cb1100forum.com/forum/showthread.php?tid=2819. Dave, what was the result of post 5 (2 May 2014)?
The bl/w wire is switched power from a 12 wire, 14 position junction, so the purge solenoid has power to it with the key on. The bl/y goes from the purge solenoid to the ECM, which must close the circuit, for the solenoid to operate. If the bl/y is grounded (rubbing on metal?) it would operate the purge without the ECM. Unprogrammed operation or stuck open would create a vacuum leak/lean operation. When unplugged, power to it should result in an audible click...no click if stuck open.
The canister itself is so buried, I thought I did not have one, but with the center stand down, looking up forward and higher than the voltage regulator, popgun educated me on its location.
To take the evap system completely out of operation, for testing, you may want to simply block off the vacuum line from the purge valve to the throttle body assembly, by removing the hose towards the left side of the bike and blocking it. It goes 90 degrees from horizontal to vertical and I cannot see its ultimate connection, without removing my fuel tank.
Will email a photo to Max and Peter, if they want to post.
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Go to the right side of your motorcycle and look just forward of the breather cover and under the throttle body. It is in line with that round disk that some people glue a quarter to. The connector for it is right there and easily accessable.
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I ran out of my 60 minute editing limit, but I mentioned in an email to popgun, Max and Peter that I would check into the PAIR air induction control solenoid valve as another possible issue. It allows filtered air from the air box to be drawn into the exhaust system. I do not see how this could be an issue with fueling. It simply reduces unspent fuel and increases the life of the catalytic converter.
I did block it on my 2012 Triumph Bonneville to reduce bluing of single wall exhaust pipes, but see no performance benefit to blocking or removal and doing so would likely be harmful to the catalytic converter.
We now resume our normal programming from Max...
10:14 Saturday morning in Nevada and 7:14 Sunday morning in Auckland.
(02-03-2018, 03:40 AM)Lord Popgun_imp Wrote: Go to the right side of your motorcycle and look just forward of the breather cover and under the throttle body. It is in line with that round disk that some people glue a quarter to. The connector for it is right there and easily accessable.
Included you in the photo email, although you are no longer set up to post photos. Would like to give credit to the forum member who first suggested the purge valve, but I am not finding the post.
Until Dave checks it out, it seems a very likely candidate and fits into my vacuum loss concerns and I am not finding a DTC for it. Wonder if unplugging it results in a CEL?
If it is the issue, be curious to know if the valve is sticking open or if programmed operation. When it is running and in lower than normal idle, I'd be inclined to tap it with something (screwdriver handle, etc.)
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(02-03-2018, 02:50 AM)SportsterDoc_imp Wrote: Preliminary to a further reply by Max:
1. The ECM has an internal 5 vdc poower supply for sensors. The black/yellow output is going to be less with engine off for two reasons:
a. With key on, but engine not running, there is electrical drain, especially from the headlight, sagging the voltage.
b. With engine running, the 3 phase alternator is recharging the battery at 13.8 to 14.8 volts.
2. I am remain concerned about a vacuum leak, such as the two vacuum hose fittings or a poor electrical connection. However, a poor connection should result in a DTC:
12-1 for fuel injector 1
13-1 for fuel injector 2
14-1 for fuel injector 3
15-1 for fuel injector 4
29-1 for IACV, etc.
3. The earlier suggestion about the evap canister purge is worth considering. Max may have a different approach, but I would be inclined to unplug the "evap purge control solenoid valve". Wires are bl/w to junction and bl/y to ECM A29. That position is labeled PCS on the factory schematics. No clue as to when the ECM triggers a purge (definitely engine running and full operating temperature, maybe minimum RPM?), but be interesting to take that out of the picture. This thread has a clue as to its location (easily seen in front of airbox from right side-easy to unplug electrical connection) and another clue for this saga: http://cb1100forum.com/forum/showthread.php?tid=2819. Dave, what was the result of post 5 (2 May 2014)?
The bl/w wire is switched power from a 12 wire, 14 position junction, so the purge solenoid has power to it with the key on. The bl/y goes from the purge solenoid to the ECM, which must close the circuit, for the solenoid to operate. If the bl/y is grounded (rubbing on metal?) it would operate the purge without the ECM. Unprogrammed operation or stuck open would create a vacuum leak/lean operation. When unplugged, power to it should result in an audible click...no click if stuck open.
The canister itself is so buried, I thought I did not have one, but with the center stand down, looking up forward and higher than the voltage regulator, popgun educated me on its location.
To take the evap system completely out of operation, for testing, you may want to simply block off the vacuum line from the purge valve to the throttle body assembly, by removing the hose towards the left side of the bike and blocking it. It goes 90 degrees from horizontal to vertical and I cannot see its ultimate connection, without removing my fuel tank.
Will email a photo to Max and Peter, if they want to post.
Suggestion AS TO PCSV only
Make a long test short::
1* test condition:: engine hot/normal operating temp and NORMAL RPM (1050)
2* disconnect vacuum hose **that goes from PCSV to Th. body/intake manifold - NOT to canister = this will create vacuum leak or as if PCSV were stuck in open position (normally closed) and register RPM change. Please
3* Do not bother any other tests with EVAP/PCSV for now.
** careful, not to break nipple to PCSV
pb
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The manual does not show a fault code for the purge valve. I can’t find anything explaining when it purges either, or if it it just energized all the time. I could find that out easily with a meter though.
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(02-03-2018, 04:27 AM)Lord Popgun_imp Wrote: The manual does not show a fault code for the purge valve. I can’t find anything explaining when it purges either, or if it it just energized all the time. I could find that out easily with a meter though.
We already know there is NO DTC for EVAP/PCSV,,just want to see if in case the PCSV gets stuck open at normal idle there is significant RPM droppage
pb
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Max, popgun, Doc, and peterbaron - thank you all so much for all you help! Right now I need to focus my attention on repairing my truck, so I won't be able to perform any more tests on the CB this weekend. Except, I just purchased some contact cleaner (don't they sell this stuff in a smaller than $9.99 size?) and I sprayed the TPS connection. I will ride the bike later today. Thank you all again.
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Thanks for the input guys, i like peter's idea about the valve, i found a picture that explains where the vacuum lines attach, i guess you want to take off the hose at the back that is hard to get to?
the valve is the blue/silver thing on the top right without cannister hose.
i wonder when this valve operates, can we make dave's life easier by disconnecting the hose at the front and opening the valve?
Actually looking at the picture is it not easier to pull one of the outer vacuum hoses off the throttle body if it is just the effect it has that we are after?
Also wondering if we should look at o2 sensor voltage at some point?
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Based upon emails from Max And Peter, I am going to back-off.
Max still has some concerns about the TPS and this is his thread.
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First, thank all of you guys for your support! I really, really appreciate all the time and effort you gentlemen are putting into helping me resolve this issue.
Update: Sprayed the TPS connector with electrical cleaner Saturday. Put 180 miles on the CB Sunday; ½ freeway, ½ mountain / back roads. Temperature was in the upper 70’s, and the elevation change was from sea-level to 4,000 feet. Averaged about 80 mph on freeway for 40 miles. Bike ran perfect. Only turned it off twice and restarted, and maybe 10 stoplights. Perfect 1,050 RPM idle each time.
Here’s some information that might help shed some light: My bike initially had a high RPM (1,400 RPM) issue, which I haven’t experienced in over probably 18 months now. When I was experiencing a high idle condition and I pulled to the side of the road to try anything I could to cure it. I turned it off and on, using the key. I turned it off and on with the kill switch. I turned it off, and then performed the TPS reset process. I blipped the throttle with the engine running, revving it as high as 6,000 RPM. Nothing helped. But suddenly, almost like someone flipped a switch, the RPM dropped, and the engine stalled. When I restarted it I believe that this was the first time that I ever experienced the low RPM idle condition. I am not 100% sure, but this may have been the last time my bike ever experienced the high RPM idle, but now began the low RPM idle condition. So I believe that whatever is causing my low RPM idle must have a root cause related to something that has the potential to change quickly, and that something has the ability to cause both a high and low RPM idle condition. What can change quickly? An electrical connection? The electrical output of one of the sensors? I don’t think it would be a vacuum leak, because it resulted in both a high and low idle condition.
I will look into the EVAP purge control valve, recommended by Doc. Unfortunately, right now I am committed to a lot of OT at work, so I don’t have time in the evening, and this weekend is the Supercross. I can put off the fork seal replacement and steering head bearings replacement on my VFR, and the head gasket replacement on my car, but I won’t be able to get back to working on the CB11 for at least a week. I do plan to ride the CB11 tomorrow evening, and I will report any issues.
Doc, the loud noise I reported when I first turn on my key (that you asked me about) seems to have gone away. I still hear the sound of the fuel pump and (I think) IACV cycling when I turn on the key, but not as loud as it did on that one occasion.
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