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Streetfighter 1098S idle speed issues

8K views 25 replies 7 participants last post by  Hejnfelt 
#1 ·
Hello everyone! I will try to explain everything as well as I can due to English is not my native language. If there is something I do not explain well tell it to me and I will explain it again...

1- I bought my bike with 31000kms and it was working perfectly at that time.
2- After a couple or three weeks, the idle speed started being variable and very high. After filling up the gas tank... problem solved :confused:. Just one day with that idle speed issues.
3- I had no more problems with the bike until a couple of months ago (I have been riding like 2 months without problems). Idle speed issues again: very variable and very high. Sometimes idle speed is OK at approximately 1400RPM but most of the time it is around 2000RPM and sometimes it has peaks up to 2600RPM. Yes, it is crazy.
4- After explaining this problem to the former owner, he told me that the bike did not pass the 24000km revision (or 2 years), so the valve adjustment was not done... So I took the bike to my trust workshop and he did the valve adjustment and everything it needed (he also changed air filter).
5- Idle speed issues still there, so he changed my ECU with another ECU, reflash that ECU with a compatible map for my bike and voilà, problem solved, so he told me to pay a lot ($$$) to fix that definitely.
6- After reading a lot on this and other forums and the help of a lot of great people, I decided to do it myself as it was way cheaper ($). I bought a Ducati 1098 SBK ECU almost new as that bike was fitted with a termi system and the cables needed.
7- Once I had everything at home (yesterday) I first backed up my original ECU, then flashed the DP map and tested the bike. Still idle issues. I replace my ECU with the one I bought, remap it with the same DP map and... still idle issues.
8- And now I do not know what to do... this problem is making me ill...

Answering @idaka questions from the "ECU maps repository" thread:

TPS-Reset done?
Idle speed is regulated via the IdleStepper.
Check, if something is leaky, and the engine gets "wrong" air.
Check with GuzziDiag/IAW Diag Airpressure/AirTemp/EngineTemp.
There are Air-Screws at the ThrottleBody, maybe,someone has changed here?
Regards
Yes, I did reset the TPS.
I do not know how to check if the engine gets "wrong" air. If it can be using GuzziDiag I will check it this afternoon after leaving work. The normal values are those that appear at the attached screenshot? I remember that my Throttle, after reseting, was set to 2.50º or 2.60º.
I do not know what are air-screws at the throttle body, I will do some research about it...

Thank you to all who provide some type of help in advance, I will appreciate it very much!
 

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#6 ·
My problem was intermittent, I found it because fuel was leaking out the TPS. I didn't have to check voltage. Do a search, I have pictures of the replacement procedure on the site. Eventually replaced the entire throttle body unit with a used 1098 unit because the shaft seal was leaking. So far 20,000 miles on it with no problems.
 
#7 ·
Nice, I found the thread you started about the TPS. But I will first check for ECU errors, try to get info about all sensors and try to catch if there is some sensor failing. If that does not show me anything clear, I will get into air bleed screws as I have been reading that some users have had problems with idle speed and that thing solved the issue.

Do you know how to get easy access to that screws without dismount half of the bike?

Thanks!
 
#8 ·
Update 1

OK, after getting home I connected the bike again. Here is what I found out... I uploaded some videos to my Google Drive.

1- I connect bike and turn engine on. TPS seems crazy. I do not know if that fluctuation is normal but it does not seem to be... At second 31 I accelerate until second 41. Just a little bit to see how TPS reacts. At 1:27 I accelerate again and let the throttle go down by itself. I do it again at 1:34 and 1:40.

https://drive.google.com/file/d/0B8sfHKElaD5VTDlrZnRobF9KQlU/view?usp=sharing

2- I reset TPS and it seems that RPM are now perfect.

https://drive.google.com/file/d/0B8sfHKElaD5VSXh2bTVMZjVqVWc/view?usp=sharing

3- I go out to fill the tank up with gas (I filled it up TWO days ago, I have only ridden 62kms -39 miles- and the yellow indicator has lit) and RPM go crazy again as soon as I get out of my garage. After filling up the tank, I stop an record another video. As you can see, RPM over 1650 all the time... At minute 1:04 I accelerate a little bit and stop.

https://drive.google.com/file/d/0B8sfHKElaD5VVndzaHFlZFZkR2s/view?usp=sharing

4- Once at home and WITHOUT touching anything nor connecting anything to the bike goes up to 2200RPM.

https://drive.google.com/file/d/0B8sfHKElaD5VRXNRdjh3OVRicUU/view?usp=sharing



This shit is driving me nuts... It seems impossible to fix. Its behavior is completely random. It does exactly the same cold and hot. Maybe RPM are perfect, then peak to 2200 or something like that and then stable around 1900...

And sorry about the video quality, I uploaded 1080 but now it is only 360...
 
#11 ·
Yes idaka, it was full or, at least, almost full. I filled the tank Tuesday morning and yesterday afternoon, after 62km ridden, light on.

Before this idle speed problem, I used to ride just like you, between 175 and 200 approximately...

I don't understand your post. 5 & 6. Did the mechanic fix it or not? Did he just claim he could fix it and you decided to do it yourself?

I certainly wouldn't have done anything with the ECU without being totally convinced I didn't have a vacuum leak between a throttle body and head or at one of the throttle shafts. Unless your bike has an ECU controlled idle air valve, the ECU would not have anything to do with since it couldn't put more air into the engine.
Yes maybe it is a little bit confusing...

The mechanic tried to spot the problems, and he thought two possibilities:

1- ECU issues
2- Something related to fuel, I do not remember what exactly, but the brand new part from Ducati costs like $900 or something like that, he told me.

He called me to explain me the situation and I decided him to make some tests with the ECU (cheaper thing). So he replaced my bike's ECU with another one so that if the idle speed issue gets fixed, that means the problem is the ECU. He did that but just to test, because the definitive solution was to get a used ECU, remove immo and remap with the appropriate map for my bike paying like $560.

He was sure that the problem was the ECU as when he replaced it, idle speed was normal (I am almost sure that it was casuality, as sometimes the fucking bike keeps idle speed perfect). As soon as he tested that out, he called me to confirm that ECU was the problem and I decided to do it myself as it was lot cheaper (ECU + cables =~ $180).

You are right about not touching ECU before being sure those things are discarded, but I am a complete noob about this topic and I have been visiting that mechanic for 4 years and I have never had any problem with him. Very honest and always explaining everything he has done to the bike. So I though: "If he is that sure, for sure that is the problem". But shit happens...



Thank you to both of you, but I think I will take the bike to the official service... I am afraid they keep the bike in a loop testing without success and get me into a paying loop...
 
#10 ·
I don't understand your post. 5 & 6. Did the mechanic fix it or not? Did he just claim he could fix it and you decided to do it yourself?

I certainly wouldn't have done anything with the ECU without being totally convinced I didn't have a vacuum leak between a throttle body and head or at one of the throttle shafts. Unless your bike has an ECU controlled idle air valve, the ECU would not have anything to do with since it couldn't put more air into the engine.
 
#12 ·
The least likely problem is the ECU . Check the easy stuff, cables, etc. There is a stepper motor on the throttle body, check the hoses. If you can, swap out the throttle bodies with a loaner. EBay has complete used ones for around $150. Does the bike surge while you are riding it?
 
#13 ·
Well, as my mechanic told me that, I just did what he would have done to fix it...

OK, I write down everything that you tell me so that I can tell him.

And I do not understand what you mean with "surge". Even Google Translate does not help me to understand it. Can you use other words please?

Thank you!
 
#16 ·
Don't give up buddy, should be an easy fix :)

When you turn the key on, you hear the fuel pump prime. Then if you turn the key off, you should hear the idle stepper motor working for a second or two. Do your bike make this little noise when you turn the key off?

My first guess would be this idle stepper (part of the throttle body assembly), the tps sensor (because yours seems to be fluctuating on idle (where on my bike it's completely stable) or maybe a leaky injector.

Good luck!
 
#17 ·
I have recorded a video so that you can hear how the idle stepper motor is working as I do not know if that sound is normal. For me, when turning off the bike, it sounds like is gets stuck or something like that, but I am not sure as I said I have no idea... Could you please tell me if that sound is normal?

There you go: https://drive.google.com/file/d/0B8sfHKElaD5VUklCTFJndlJaaUE/view?usp=sharing

Yesterday afternoon I went to speak with my mechanic and he told me that the TPS sensor seems to be OK, but as it is fluctuating... I do not know, it is really strange. Is there any test I can do to make sure it is working properly?

I do not want to give up but I have not enough experience doing this type of things and I do not want to make this problem get even worse or blow up something else... Electronically I am not very afraid, but with mechanical things...

Thank you very much!
 
#20 ·
OK, problem solved!!

Finally it was a 3 different components problem:

1- ECU
2- TPS
3- Servomotor emulator

Explanation:

1- ECU was not able to regulate the idle speed. After changing it and remap with DP map, new ECU was able to do it but problem persist...
2- TPS was destroyed... it was totally broken...
3- Servomotor emulator shares mass with TPS and it is no more useful as DP map cancels the error when servomotor is not installed.

Thank you very much to you all for the help!
 
#21 ·
Problems again...

The idle speed keeps being crazy after all the changes that were made...

I brought the bike to an official Ducati workshop and they told me that the TPS sensor is reporting wrong data. I told them that it was already changed and then they told that maybe it is an ECU problem. I told them, again, that it was already changed and they have no idea where to go from here...

This is driving me crazy... any other ideas?
 
#24 ·
Have you tried spraying the throttle body / head junction area with water using a spray mist bottle while it's idling high? If the idle changes you've got a vacuum leak. TPS readings shouldn't be all over the place, could be bad wiring or bad sensor or bad connections.

Also have you replaced fuel filter and checked tank vent for vacuum?
 
#25 · (Edited)
Well, after more than a year from my last message, still having issues. Sorry, I completely forgot about this thread...

At the workshop they've done everything we've spoken here. They say they've checked and it's not a vacuum leak. They've told me that when they turn on the bike, the TPS reports that the throttle is halfway open, so it injects A LOT of fuel and then the motorbike does not start. The problem is the TPS, that's for sure. Every time they've replaced and reset the TPS only, the motorbike runs perfectly for some time until it starts the same problem of faulty TPS again.

They are saying that they recommend trying to replace the entire throttle body and of course, that will fix the problem at least temporarily because by doing that, there will be a new TPS, but if the problem appears again... it's going to be a fucking pain because I'd have paid $1500 for that part for nothing. And they are not giving the part's money back despite their wrong diagnose made me spent that huge amount of money.

Again, the TPS is the one reporting wrong data. The TPS is mechanically perfect, according to them. Knowing that, what can it be that's fucking the TPS readings up? You said "TPS readings shouldn't be all over the place, could be bad wiring or bad sensor or bad connections." and I complete agree with you, but those workshop guys have no idea what they are doing and I have no other official Ducati workshop near my place.

If it's the bad wiring, where is TPS wiring connecting to?
What can a bad connection be?
How can they detect the electrical failure?

I've told them about it but they complain that they have tools but they are not fully functional as Ducati blocks some of the functionality. This is driving me crazy. Almost two years already with this problem...
 
#26 ·
I know this is an old thread, but looking through all these posts there does not seem to be a solution posted, so want to add mine.

Have you considered replacing your throttle cables or adjusting them? I had the exact same issue. Sometimes mine would be at the normal 1600-1650 rpm idle and sometimes, especially when warm after a spirited ride, it would be idling closer to 2000rpm. For me it seemed obvious that something was up with the throttle and after a tiny adjustment giving a bit more slack, this issue has been resolved for me.
 
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