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(01-26-2018, 04:46 AM)max_imp Wrote: Dave, looking at another video that i did not use the 700 rpm started at 0.80 volts and by 0.925 volts the engine died at 450 rpm.
Question for you; what can cause the tps sensor signal wire ( black/red ) voltage to rise above 0.5 volts if the tps is in the idle position?
The 5 volt supply to all sensors is generated and stabilized by a special circuit within the ecm ( computer ) and will be maintained at 5 volts exactly even at very low or high battery voltage, a sign of the 5 v dropping below operating condition is the meters and fuel pump cycling after and during an engine start, so even a bad battery will result in a stable 5 v supply.
Max: Please verify, but I understood you to think that no further testing, beyond resistance tests, are necessary, which would let us move on to the IACV...which has only one DTC:
Doc, that is a very important question;
The tps voltage/resistance testing was LIKELY NOT TO SHOW A FAULT.
The important thing is to eliminate the tps/wiring fault all together by disconnecting it, only when we determine the fault has disappeared it's time to find the actual cause.
That is why i asked Dave to unplug it and ride for an extended period at least 5 times, starting with post 1 of this thread, after 4 weeks i am still waiting for that moment.
The trick with intermittent faults is to wait until it happens frequently enough to enable to locate the source of it,
waste of time testing something that works fine at the time of testing, you need to catch it when the fault is present.
As you may remember jdvalero fixed his high idle to date by locating 2 "low tps voltage " fault codes and traced it back to a rotated pin inside the tps connector; http://cb1100forum.com/forum/showthread....#pid187614 if you look at post 52 he shows the connector; http://cb1100forum.com/forum/showthread....#pid187944
For tps- idle relation have a look at this video, you can spool to 26 minutes into the video if you don't want the whole thing, the guy with the cap is keith, he is the clever dude with a lot of experience; https://www.youtube.com/watch?v=NWdOASlI0GA
max
Max
This is your thread, so continue to coach Dave through the completion of the TPS testing. An intermittent issue is very much a challenge.
I emailed you my 2 cents on IACV testing, when you are ready.
It is up to 58 F, so I am leaving for a ride.
Forecast is for a high of 69 F, Mon and Tue!
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That is why i asked Dave to unplug it and ride for an extended period at least 5 times, starting with post 1 of this thread, after 4 weeks i am still waiting for that moment.
Max. I have ridden my bike twice with the TPS unplugged, and reported it on this forum both times. The first time around my neighborhood, the second time while in a college parking lot. Granted, I did not cover a lot of miles, but the bike is unsafe to ride on the street with the TPS unplugged due to the fact the engine starts cutting out at 2,800 RPM, and completely shuts down at 3,000 RPM. I really appreciate your help, and I will take the bike over to the college tomorrow and ride it around with the TPS unplugged. How many miles would be an acceptable test? Also, exactly what am I looking for? I reported that the idle speed with the TPS unplugged was approximately 800 RPM. Both of the rides I did with the TPS unplugged were performed when the bike was experiencing the low RPM condition. If my bike is running normally (1,050 RPM idle), and I unplug the TPS and ride it will this generate the results we're looking for? Please advise. Thanks again for your support Max.
1 if your bike runs better after the tps is disconnected that would be an indication the tps is bad.
My bike did NOT run better after unplugging the TPS.
It appears ok to drive this way but just to be on the safe side i would not recommend long periods unplugged riding.
If you are not recommending long periods of unplugged riding, then what are we talking about here, a few miles?
Please advise.
Thank you.
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(01-26-2018, 11:49 AM)Dave_imp Wrote: That is why i asked Dave to unplug it and ride for an extended period at least 5 times, starting with post 1 of this thread, after 4 weeks i am still waiting for that moment.
Max. I have ridden my bike twice with the TPS unplugged, and reported it on this forum both times. The first time around my neighborhood, the second time while in a college parking lot. Granted, I did not cover a lot of miles, but the bike is unsafe to ride on the street with the TPS unplugged due to the fact the engine starts cutting out at 2,800 RPM, and completely shuts down at 3,000 RPM. I really appreciate your help, and I will take the bike over to the college tomorrow and ride it around with the TPS unplugged. How many miles would be an acceptable test? Also, exactly what am I looking for? I reported that the idle speed with the TPS unplugged was approximately 800 RPM. Both of the rides I did with the TPS unplugged were performed when the bike was experiencing the low RPM condition. If my bike is running normally (1,050 RPM idle), and I unplug the TPS and ride it will this generate the results we're looking for? Please advise. Thanks again for your support Max.
1 if your bike runs better after the tps is disconnected that would be an indication the tps is bad.
My bike did NOT run better after unplugging the TPS.
It appears ok to drive this way but just to be on the safe side i would not recommend long periods unplugged riding.
If you are not recommending long periods of unplugged riding, then what are we talking about here, a few miles?
Please advise.
Thank you.
---------------Yes, that is exactly the best time to test, if the tps is unplugged and the idle rpm does--- not change ---that is the outcome we are looking for.
My bike did NOT run better after unplugging the TPS.
---------------------Yup, agreed, but was the idle steady?
It appears ok to drive this way but just to be on the safe side i would not recommend long periods unplugged riding.
If you are not recommending long periods of unplugged riding, then what are we talking about here, a few miles?
Please advise.
-----------------------Would say a day long is not bad but a week is not advisable, if you can ride for longer than is usually necessary to get idle issues that would be nice.
having trouble finding the right format for answering in the right way so put some lines in front of the answer instead, still learning here.
max
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(01-26-2018, 01:14 PM)max_imp Wrote: (01-26-2018, 11:49 AM)Dave_imp Wrote: That is why i asked Dave to unplug it and ride for an extended period at least 5 times, starting with post 1 of this thread, after 4 weeks i am still waiting for that moment.
Max. I have ridden my bike twice with the TPS unplugged, and reported it on this forum both times. The first time around my neighborhood, the second time while in a college parking lot. Granted, I did not cover a lot of miles, but the bike is unsafe to ride on the street with the TPS unplugged due to the fact the engine starts cutting out at 2,800 RPM, and completely shuts down at 3,000 RPM. I really appreciate your help, and I will take the bike over to the college tomorrow and ride it around with the TPS unplugged. How many miles would be an acceptable test? Also, exactly what am I looking for? I reported that the idle speed with the TPS unplugged was approximately 800 RPM. Both of the rides I did with the TPS unplugged were performed when the bike was experiencing the low RPM condition. If my bike is running normally (1,050 RPM idle), and I unplug the TPS and ride it will this generate the results we're looking for? Please advise. Thanks again for your support Max.
1 if your bike runs better after the tps is disconnected that would be an indication the tps is bad.
My bike did NOT run better after unplugging the TPS.
It appears ok to drive this way but just to be on the safe side i would not recommend long periods unplugged riding.
If you are not recommending long periods of unplugged riding, then what are we talking about here, a few miles?
Please advise.
Thank you.
---------------Yes, that is exactly the best time to test, if the tps is unplugged and the idle rpm does--- not change ---that is the outcome we are looking for.
My bike did NOT run better after unplugging the TPS.
---------------------Yup, agreed, but was the idle steady?
It appears ok to drive this way but just to be on the safe side i would not recommend long periods unplugged riding.
If you are not recommending long periods of unplugged riding, then what are we talking about here, a few miles?
Please advise.
-----------------------Would say a day long is not bad but a week is not advisable, if you can ride for longer than is usually necessary to get idle issues that would be nice.
having trouble finding the right format for answering in the right way so put some lines in front of the answer instead, still learning here.
max
I don't know if this is the only way, but if you hit "reply" leave the following--but with the brackets [...] before "quote" and after the number 3' :
quote='Dave' pid='193947' dateline='1517017773'
text from other poster that you want to quote goes here
...and then leave this as it appears:
[/quote]
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Max & Doc: I am going to ride the bike today to runs errands, and bring my VOM along. If/when the low idle conditions appears I will immediately stop and measure the voltage at the TPS Black/Red connection. I will do this with the engine running, and the TPS plugged in, and then repeat it with the engine off. Each time I will twist the throttle to see if/how the voltage changes. Hopefully this will provide some useful information. If the low idle condition does not appear I will unplug the TPS and ride it for several miles and see what happens. What do you guys think? I'll report back this evening.
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(01-27-2018, 01:14 AM)Dave_imp Wrote: Max & Doc: I am going to ride the bike today to runs errands, and bring my VOM along. If/when the low idle conditions appears I will immediately stop and measure the voltage at the TPS Black/Red connection. I will do this with the engine running, and the TPS plugged in, and then repeat it with the engine off. Each time I will twist the throttle to see if/how the voltage changes. Hopefully this will provide some useful information. If the low idle condition does not appear I will unplug the TPS and ride it for several miles and see what happens. What do you guys think? I'll report back this evening.
BACK PROBE BETWEEN SENSOR SIGNAL AND SENSOR GROUND (IDLING & PLUGGED IN) TO GET TPS READING......
AND AGAIN, ENGINE OFF WITH IGN & KILL SWITCH ON = AS PER YOUR STATEMENT
SO WE EXPECT TWO (2) READINGS WITHOUT CHANGING PROBE POSITION, and without disconnecting TPS , PLEASE
PIN 1 - NEGATIVE
PIN 2 - SIGNAL
PIN 3 - Power SUPPLY (5V)
pb
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(01-27-2018, 01:14 AM)Dave_imp Wrote: Max & Doc: I am going to ride the bike today to runs errands, and bring my VOM along. If/when the low idle conditions appears I will immediately stop and measure the voltage at the TPS Black/Red connection. I will do this with the engine running, and the TPS plugged in, and then repeat it with the engine off. Each time I will twist the throttle to see if/how the voltage changes. Hopefully this will provide some useful information. If the low idle condition does not appear I will unplug the TPS and ride it for several miles and see what happens. What do you guys think? I'll report back this evening.
Dave, that sounds real good om both idea's, if you can capture it in the act and even take a picture and or video that would settle it.
Actually pb's post made me think, if you can measure all three pins whilst in low idle you may be able to prove if the ground return ( black green ) is higher than 0 volt or not, if it is more than 0 volt that would point to bad connection in ground return path to ecm, you can even measure if the engine has stalled.
To give you an idea about the current through the tps circuit( 5 v divided by 6000 ohm ) is less than 1 mA, a lot can go wrong at such a low current.
One idea i had was to make a gadget that can be plugged in between the tps and connector that would indicate an led on over 0.6 volts, easy to do since a transistor switches on at 0.6 volts, all you need is 2 resistors an led and a npn transistor, but the vom is of course much more accurate.
Thank you, pb and pdedse; max
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(01-27-2018, 04:25 AM)max_imp Wrote: (01-27-2018, 01:14 AM)Dave_imp Wrote: Max & Doc: I am going to ride the bike today to runs errands, and bring my VOM along. If/when the low idle conditions appears I will immediately stop and measure the voltage at the TPS Black/Red connection. I will do this with the engine running, and the TPS plugged in, and then repeat it with the engine off. Each time I will twist the throttle to see if/how the voltage changes. Hopefully this will provide some useful information. If the low idle condition does not appear I will unplug the TPS and ride it for several miles and see what happens. What do you guys think? I'll report back this evening.
Dave, that sounds real good om both idea's, if you can capture it in the act and even take a picture and or video that would settle it.
Actually pb's post made me think, if you can measure all three pins whilst in low idle you may be able to prove if the ground return ( black green ) is higher than 0 volt or not, if it is more than 0 volt that would point to bad connection in ground return path to ecm, you can even measure if the engine has stalled.
To give you an idea about the current through the tps circuit( 5 v divided by 6000 ohm ) is less than 1 mA, a lot can go wrong at such a low current.
One idea i had was to make a gadget that can be plugged in between the tps and connector that would indicate an led on over 0.6 volts, easy to do since a transistor switches on at 0.6 volts, all you need is 2 resistors an led and a npn transistor, but the vom is of course much more accurate.
Thank you, pb and pdedse; max
Dave, that sounds real good om both idea's, if you can capture it in the act and even take a picture and or video that would settle it.
Actually pb's post made me think, if you can measure all three pins whilst in low idle you may be able to prove if the ground return ( black green ) is higher than 0 volt or not, if it is more than 0 volt that would point to bad connection in ground return path to ecm, you can even measure if the engine has stalled.
To give you an idea about the current through the tps circuit( 5 v divided by 6000 ohm ) is less than 1 mA, a lot can go wrong at such a low current.
One idea i had was to make a gadget that can be plugged in between the tps and connector that would indicate an led on over 0.6 volts, easy to do since a transistor switches on at 0.6 volts, all you need is 2 resistors an led and a npn transistor, but the vom is of course much more accurate.
Thank you, pb and pdedse; max
VIDEO WOULD BE EN EXCELLENT IDEA AS MAX SUGGESTED, THANKS 
pb
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So I put 45 miles on the CB yesterday running errands, (30 miles on the freeway, 15 miles around town) hoping that I could make some progress diagnosing the idle problem. Before riding I rechecked the voltage at the TPS black/red connection with the bike off, sensor connected, and it measured .5 volts with the throttle closed, and it smoothly transitioned to 4.3 volts with the throttle wide open (it measured 4.4 volts with the throttle wide open the last time I measured it). I then checked the voltage with the engine started: .5 volts at idle (1,400 RPM cold), and a smooth increase as I twisted the throttle. I left the sewing needle plugged into the TPS connector, removed the battery cover (for quick access to the battery negative terminal), and packed my VOM in the trunk and set off. Unfortunately the low idle condition never occurred, and I did not make any additional measurements. I made four stops, where I turned the engine off, and probably over a dozen red lights, where the ide speed was a perfect 1,050 RPM each time. I am hoping the wife will agree to go for a ride today where we can rack up some good miles, and I will bring the VOM along (the sewing needle is still plugged into the TPS connection. I’ll make the measurements suggested by peterbaron also. Thanks for all your help guys.
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(01-28-2018, 01:23 AM)Dave_imp Wrote: So I put 45 miles on the CB yesterday running errands, (30 miles on the freeway, 15 miles around town) hoping that I could make some progress diagnosing the idle problem. Before riding I rechecked the voltage at the TPS black/red connection with the bike off, sensor connected, and it measured .5 volts with the throttle closed, and it smoothly transitioned to 4.3 volts with the throttle wide open (it measured 4.4 volts with the throttle wide open the last time I measured it). I then checked the voltage with the engine started: .5 volts at idle (1,400 RPM cold), and a smooth increase as I twisted the throttle. I left the sewing needle plugged into the TPS connector, removed the battery cover (for quick access to the battery negative terminal), and packed my VOM in the trunk and set off. Unfortunately the low idle condition never occurred, and I did not make any additional measurements. I made four stops, where I turned the engine off, and probably over a dozen red lights, where the ide speed was a perfect 1,050 RPM each time. I am hoping the wife will agree to go for a ride today where we can rack up some good miles, and I will bring the VOM along (the sewing needle is still plugged into the TPS connection. I’ll make the measurements suggested by peterbaron also. Thanks for all your help guys.
Still watching this...I'm pulling for you, Dave! I keep hoping that it's simply a TPS connectivity issue for you.
(01-28-2018, 01:23 AM)Dave_imp Wrote: So I put 45 miles on the CB yesterday running errands, (30 miles on the freeway, 15 miles around town) hoping that I could make some progress diagnosing the idle problem. Before riding I rechecked the voltage at the TPS black/red connection with the bike off, sensor connected, and it measured .5 volts with the throttle closed, and it smoothly transitioned to 4.3 volts with the throttle wide open (it measured 4.4 volts with the throttle wide open the last time I measured it). I then checked the voltage with the engine started: .5 volts at idle (1,400 RPM cold), and a smooth increase as I twisted the throttle. I left the sewing needle plugged into the TPS connector, removed the battery cover (for quick access to the battery negative terminal), and packed my VOM in the trunk and set off. Unfortunately the low idle condition never occurred, and I did not make any additional measurements. I made four stops, where I turned the engine off, and probably over a dozen red lights, where the ide speed was a perfect 1,050 RPM each time. I am hoping the wife will agree to go for a ride today where we can rack up some good miles, and I will bring the VOM along (the sewing needle is still plugged into the TPS connection. I’ll make the measurements suggested by peterbaron also. Thanks for all your help guys.
It woldn't dare act up with her along!
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