tps evaluating for ii issues

[pdedse]

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.

Cool.

[dave]

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.
[/quote]

Doc, I have to take this answer back. After thinking it over carefully, and taking my bike for a spin tonite, I believe that the sound of the fuel pump and the IACV when I first turn on the key varies slightly, sometimes a little bit louder than other times. I believe that the post that you're referring to, when I stated the noise was louder, it had gotten louder than what was "normal" at that time (my bike was still pretty new), and I thought the louder sound indicated a problem. I believe that initially, when my bike was new, the sound was quieter, but now, the louder sound compared to when the bike was new is the new normal.

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.

Cool.

Cool.
If only it will continue running this way!

[max]

Well Mr Dave that is the best news i have heard sofar and it is a relief to hear the good news.

As usual you come up with interesting and important bits of info in your post which i am mulling over.
i apologise to the audience for posting such a large picture which makes reading Dave's report difficult.

Please take your time to test and enjoy the bike as the states slowly get warmer.

max

[dave]

It’s back, and with a vengeance. Rode the bike in town yesterday evening about 10 miles total, running an errand and going to dinner, and it ran perfectly. Rode it tonight on my normal 60 mile round trip to visit my mother-in-law and it ran perfectly all the way there, and 29 out of 30 miles on the way home. Trip is about 26 miles of freeway each way, which are a constant 70 mph on the way home. When I pulled off the freeway and stopped at the first light the idle dropped to 700 RPM, but quickly worked its way back up to 1,050 RPM by itself. This repeated at the next two stop lights, and when I reached my driveway, 1 mile away. Instead of pulling in I rode around the neighborhood, and at the second stop the engine stalled. I restarted it, and it stalled again. I restarted it again and it stalled a third time. The only way it would stay running this time is if I held the throttle slightly open. Normally, when this condition occurs, it drops to 700 RPM, and then slowly works its way back up to 1,050 RPM; it doesn’t usually stall. I rode home, about ¼ mile away, and when I reached my driveway it did the 700 RPM to 1.050 RPM routine. I turned the bike off and put it in the garage. I am going to unplug the TPS connection tomorrow and spray it with cleaner again, and work the connection off and on to try and clean any potential corrosion.

Max – I cannot open the picture on your post #98.

[max]

See if you can open this one.
one click opens in separate window and second click enlarges the view.

This is a picture from ebay, i don't have this throttle body.



Thanks to the good advice from sportsterdoc i have labelled the hoses for clarity.

The hoses are devided in two groups; the yellow ones are vacuum for the evap system and the blue ones are connected to the Manifold Air Pressure sensor.

What may be interesting to do is disconnecting both yellow outside ones that are easy to get out.

I can start my bike with the hose disconnected and dangling free ( i have only one of these and no evap system ) and idle it with very little effect, hot or cold that is;
------------ my iacv will correct the idle rpm to maintain 1050.----------

If your bike does the same thing then the iacv is doing it's job, and normally that would be the case.
However if you have a low idle in progress, you unplug the two outside hoses and the idle rpm goes up that would mean the iacv is closed and by unplugging the hoses you bypass the iacv to try and help it by doing it's job to achieve 1050 rpm .

This should be easy to try, see if you can pull the hoses off and push them on only halfway to make it easy to pull them out.

The fact that you told us that the idle slowly comes back to 1050 could be that the valve has difficulty in opening and closing ( stuck ) and the ecm eventually gets the job done.

max

[dave]

Hi Max, I can see the picture now - perfect! Thank you! I will remove the hoses you suggest and test as you recommend and report back. Thank you so much!

[dave]

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

[/quote]
Hi peterbaron. Please excuse my ignorance. What is "AS"? PCSV = Purge Control Solenoid Valve, correct? Max is recommending that I disconnect the two EVAP system hoses (hoses identified with yellow marks in previous post), and I assume that this is the same thing as the PCSV? This seems like a pretty simple test that I can do. If my bike is running fine (1,050 RPM, warm idle) and I pull off these hoses what should I expect? I believe that Max is saying that if I pull these hoses off when experiencing a low idle condition and the idle speed increases, then this could point to a defective or sticking IACV, is this correct? Doc has suggested that I unplug the connection to the EVAP purge control solenoid valve (PCSV). Will doing this test achieve the same results as unplugging the two EVAP system hoses? This sounds like a pretty simple test that I can do also. Thank all of you guys for your continual support.

[dave]

What is "AS"?
Ok, I went back and reread this and I believe I understand it now. "AS" is not an acronym, it's the word "as", correct?

In the Honda parts break-down, the PCSV is part number 36162-PLC-003. Will unplugging the connection have the same effect as disconnecting the two hoses recommended by Max, and will disconnecting the one hose connection on the PCSV have the same effect? I will perform each of these tests, if necessary. Thank you.

[Lord Popgun]

Dave, ‘as’ is a word in his useage.

Unplugging the electrical connection will not be the same thing as removing the hoses.

Right now we are not sure when the purge valve is activated. As Max and Peter do not have one, I may play with that this weekend by just using a multimeter and trying to see when the voltage shows up to energize the PCSV.

I can also hook up my OBD tool and remove the hoses and see how the engine responds.

I’ll report my findings to Max (and Peter and Sportsterdoc) as he is pretty much the front man in our efforts here.

[peterbaron]

Dave,
"AS" forget about this...it should be written ..."as" far as to PCSV....

>>>>>>>>>>>>>>>>>>>>>>>>>>
1* test condition:: on center stand, engine hot/normal operating temp and NORMAL RPM (1050)..if for any reason is not within specs, wait until it stabilizes within..
2* disconnect THICK/YELLOW vacuum hose end **that goes from PCSV to Th. body/intake manifold = this will create vacuum leak or as if PCSV were stuck in open position (normally closed) and register RPM change....it may very, so watch it for a while..
** careful, not to break nipple to PCSV
Unplugging the electrical connection will not be the same thing as removing the hoses (Popgun is perfectly correct)

>>>>>>>>>>>>>>>>
YELLOW SKINNY HOSES DISCONNECTION...might be more difficult to achieve , since there is less access to inner throttles ??? have a look..

Max is recommending that I disconnect the two EVAP ( skinny vacuum hoses/yellow & blue, linking each th. body, Honda calls'em MAP vacuum hoses) system hoses (hoses identified with yellow marks in previous post), and I assume that this is the same thing as the PCSV?(..generally, all seems to go to intake manifold) . This seems like a pretty simple test that I can do. If my bike is running fine (1,050 RPM, warm idle) and I pull off these hoses what should I expect = YOU SHOULD SEE RPM CHANGE...watch for a while what is happening with RPM...may go up, down...

Let us know, please... before next step as per Max/SportsterDoc/Popgun

pb