CB1100 Idle speed instability problem

[Lord Popgun]

I can almost bet it is the IACV. And your dealer tech should be able to troubleshoot it fairly easily. If he has a service manual, he needs to read it.

 

[Riko_imp]

where do i find that part on the exploded view?
Genuine parts for Honda 2014 CB 1100 EX ABS - Honda

edit
I see parts 6 and 8 described as AICV.
6 is a joint and 8 is a plate...

You said the dealer has to read it, what do you mean? Via ECU diagnostics? Or is this a pure mechanical part?

 

[Lord Popgun]

Throttle body for Honda CB 1100 EX ABS 2014 - Honda

Item 4. Its called a motor assembly on the parts fiche

If they think its the TPS, the book covers troubleshooting on that too. However, you can't get it separately.

 

[Riko_imp]

Sorry to ask again. But where do i find the tps?

 

[Lord Popgun]

Sorry to ask again. But where do i find the tps?

You have to buy the entire Throttle Body assm. You really don't want to have to do that. But, to answer your question. Look at the pic and notice the arrow indicating forward. On the left side of the Throttle body ( or on the bottom right of the pic), you can see it.

If you look at the left side of your bike, just in front of the air box cover, you can see it. Has 2 screws and an electrical connector on it. The TPS is shapped just like in the parts diagram.
Just to add to the discussion. We had a TPS thread a long while back. A member said that even though the TPS is not avail from Honda, the voltage specs for it match a TPS for some car. He said it could be used. Using the min/max values in the book, it could then be adjusted to match.

Disclaimer: I have never done it as mine is ok. Do some research first.

TPS failures usually set fault codes. If they can be faulty and not cause a code to be set, well, someone else will have to address that.

 

[Riko_imp]

Thx a lot man!

Is there any way to clean the AICV or perhaps disconnect the plug and reconnect? Would that help?

I will have a look later, but I suspect the AICV is on the right hand side. If I can reach or see it is another matter.

 

[curlyjoe]

According to the service manual, you'll need to remove the fuel tank to get at the 4P connector. Is the bike still under warranty? If so, I would suggest letting the dealer solve this problem.

 

[Lord Popgun]

+1 on what Curly said.

To answer your question though, sure you could reseat the connector. Pins oxidize. You'd be surprised how many problems in electronic systems are fixed by simple connector or component reseats.

The manual even shows a test where you remove the IACV and watch it while turning the ignition key on. Even some resistance checks. I would not do any of that though if it is under warranty. And if not, you need to get a service manual, a DVOM and some electrical/electronics knowledge would help too.

 

[Riko_imp]

According to the service manual, you'll need to remove the fuel tank to get at the 4P connector. Is the bike still under warranty? If so, I would suggest letting the dealer solve this problem.

yeah indeed, I got warranty till 9th of December. (obligatory 1 year warranty for second hand vehicles)

Whats bothering me about all of this, is the fact that the Taiwanese EX owners who have the same issue, don't seem to have seen their issue resolved.
I read the comments on the Taiwanese cb1100 facebook group (lots of pics! ) and use google translate, but as far as I can trust the translation, the results aren't very hopefull.

Same on the French board.
There I saw a few members mailed to the European office: cco@honda-eu.com
And so I mailed them as well describing the problem, luckely for me the European main office, wich happens to be in Belgium
And so far nobody had received any answer.

Yesterday I talked to a guy that admired my bike and told him about my problem.
Long story short, he said its not abnormal they do not reply.
They could be waiting to reply until they got a bunch of complaints...

Ow well, whatever the case is, I'll visit my dealer.
Problem is, I can only go Friday, they have a death in the family so the shop is closed the next few days.

I do however have my mechanic who lives very close to me and he is a freak about air cooled Honda's and does custom jobs and in his shop he has always a few of those bikes he works on.
He also does maintenance service for all other bikes and scooters.

If my official dealer does not find the solution, I trust my mechanic will.

+1 on what Curly said.

To answer your question though, sure you could reseat the connector. Pins oxidize. You'd be surprised how many problems in electronic systems are fixed by simple connector or component reseats.

The manual even shows a test where you remove the IACV and watch it while turning the ignition key on. Even some resistance checks. I would not do any of that though if it is under warranty. And if not, you need to get a service manual, a DVOM and some electrical/electronics knowledge would help too.

this sounds logical, however, when I look at the way the bike handles and the conditions the problem occurs, I suspect its not a matter of a bad connection.

Because, the bike rides fine in city condition (lots of stop and go) but after 15 -20 min, the starts to drop rpm's....
And the bike is fixed as soon as I push the kill switch, than I'm good to go for another 15 min in city traffic without issues.

I think with a bad connection the bike would drop rpms from the start and not always after a certain amount of time.

I think, but I could as well reseat the connector I guess.

1 thing is for sure, I need to get myself a service manual! I'll be looking into that this evening I guess.
I've seen something on ebay where you pay 21 dollars for a PDF, with only 1 left :dodgy:
And I am not sure if that one is also for a DLX model.

Any suggestions are welcome

 

[kennyw]

May be a faulty kill switch? Since touching that seams to change things, I would inspect it as well.

 

[Riko_imp]

or the kill switch acts as a kind of reset for whatever is faulty with the idle speed?

anyway, i red it here, someone used the killswitch to make the issue (temporary) go...

I think its in this topic

 

[Riko_imp]

Okay so today I brought the bike in, and told them the issues, but they didnt know...they were clueless.
btw I just said my problem, they did not look at the bike.

Mean reason for the visit was to make an appointment, so I made a deal that at the end of this month I will bring the bike in, so they can figure it out for a whole week.
Meanwhile I will make a video to show the issue.

I fear when that week is over I will not have a 100% working as it should-bike.

At the mean time, they did make an official complaint to send of to Honda Worldwide...so the whole procedure has started about this issue I and (so many?) others (in Taiwan) have.

I feel this is going to be a long term thing to deal with.

Fortunatelly, I can ride the bike for about perfectly for about 90% of the time tbh.
If I do long trips the bike is 100%, but if I do only city riding when the issue appears, I can somewhat anticipate by pushing the killswitch, at an convenient moment. hmmm

Luckely the time the bike wants to die, there are already moments in advance you see its struggling...so its not that bad that the bike is completely unrideable and I just wont let it come so far that the bike dies.
Bottom line at this moment: anticipation is the key.

When I have made the video for my dealer I will share it here as well....I would not be surprised if the issue will arise on more EX models.

But still, this should not be happening to a brand new bike from Honda..

 

[Riko_imp]

this is the video I made that will fix my bike, do you hear this Honda, FIX THIS!!!!!

 

[fruno_imp]

Riko, this video shows the problem very well. In my opinion, this really is a safety issue!! Honda needs to look into that and maybe even do a callback when they find the root cause.

I hope the problem can be fixed for you, but I also understand your frustration about the CB.

many greetings, fruno

 

[Riko_imp]

ow well, i try to see the positives in all this

Its convenient you replied, because I was wondering if there are any cases like this to be read on the German forum?
Honda CB 1100 Forum

Could you be so kind to open a topic in the technical/ mechanical section of the board about this issue and perhaps share the video.

Same on the UK forum, no cases....on the French board however there are cases and some are showing my video to their dealer.

 

[flynrider]

Excellent video, Riko. It shows the problem very well. The part showing that the kill switch fixes the problem temporarily should provide them with a good clue as to the source of the problem.

Good luck!

 

[Elipten_imp]

That is just plain unacceptable! I hope Honda solves the issue fast. Strange only on the EX models do far.

 

[Riko_imp]

Some mechanics i spoke with strongly follow the hypothesis its bad lambda sensors.

That could explain the issue.
Giving wrong info to the ecu causing it to idle low.
Doing this only after its on temperature, so not immediately.
Using the killswitch resets the values send from the sensor.
No error codes on the ECU.

Thinking about perhaps going the O2 eliminator way....

But later today I'll to disconnect the battery since that solved the issue for someone according to my taiwanese facebook connections..i doubt this is true, but I can only exclude that option by trying.

 

[kmoney_imp]

Some mechanics i spoke with strongly follow the hypothesis its bad lambda sensors.

That could explain the issue.
Giving wrong info to the ecu causing it to idle low.
Doing this only after its on temperature, so not immediately.
Using the killswitch resets the values send from the sensor.
No error codes on the ECU.

Thinking about perhaps going the O2 eliminator way....

But later today I'll to disconnect the battery since that solved the issue for someone according to my taiwanese facebook connections..i doubt this is true, but I can only exclude that option by trying.

Most EFI systems run idle and WOT in open loop mode, and only use O2 sensors for part throttle mixture control. It's possible the CB is different, but I would be surprised if it was the oxygen sensor causing this problem.

 

[curlyjoe]

Riko, it's interesting that turning the kill switch on/off temporarily solves the problem. I noticed in the video, you didn't try turning the ignition off and then on. Will that also solve the problem temporarily or is the kill switch the only thing that works?

Good video and I think it's good that you posted it on youtube. It may be more effective in getting Honda execs attention than going through "proper" but nonpublic channels.