I have a 2021 scrambler Nightshift that has run only 6000 km and I am having some cold start issues. When starting the bike when it is cold it will not handle throttle or load without dying The problem is similar to as if I killed it with letting the clutch out to quick. it is if it cannot handle the load. The same happens when I jerk the throttle under the same conditions and provokes the engine a bit, then it just dies as well. It seems to me as the problem is somehow connected to the cold start program that mixes fuel and air. However, my understanding is that this is the same program that is being run each time and is not really adjusted. Is there anyone out there with any insight in to this? I have an OBD2 bluetooth dongle and adapter to connect to the bike, but I am having a hard time finding any apps that can read Ducati code, in case anything is showing up as fault codes. Just for clarification. the issue is gone after just 50-100 meters of driving and the engine has adjusted to any load, and if the bike is warm there is no issue at all. Any help, advice or input is welcommed. With best regards Tobias
For that model year and bike I think you’re going to need something such as OBDStar iScan for Ducati or find a mechanic who has Texa. I don’t think any of the free software variants out there eg JPDiag will be able to interface with the ECU (but I’m open to being corrected). It does sound like there could be an issue with the stepper motor which controls the choke/cold start mechanism, but it could just as easily be a faulty input from any one of a number of sensors on the engine.
Does the exhaust have a valve on it and if so is it opening and closing ok? Should run through an open/close cycle when you switch the ignition on?
It might be, but I am not too familiar with the function of this part. I have however heard mentions of the throttle position sensor (tps) that needs calibration. also what is strange is that this only occur right after start, and it fairly quickly goes away, but it's annoying enough that every time I take off, i need to struggle a bit.
I suspect there's been an auto-correct error in @Derek 's post and he meant for the word 'idle' to appear but the computer corrected it to 'idea'. The idle control valve or stepper motor adjusts the air/fuel mixture at start up by choking off the air intake in a series of decreasing steps (as determined by the programme within the engine control unit) so as to enrich the mixture when the engine is cold and bring it back to 'normal' mixture as the engine warms up. As said above, my money's on that rather than the TPS.
Hello @West Cork Paul and @Derek Thank you for the clarification. I'll have a look at the idle control valve. Would you have any tips on how I can look for correct function?
It is an electrically operated servo valve. At ignition switch on you should hear it move to the cold start position. They are known to sometimes get gummed up. Carb cleaner can be used to free them off.
A small update. I found the part and sent a few blasts of carb cleaner through all three wholes. No dirt or discoloration came out. I see or hear however no movement what so ever when turning on the ignition. (Not turning the engine) should the starter switch be used as well to turn the engine? Another question. The electrical connector is either super stuck, or there are some sort of seal holding it super hard because it will not move.
Update. I got the electrical connection of as well. Upon reconnecting the actuator to the bike I got it to move. I also noticed that it moves when throttle is applied somewhat. This leads me to believe that the part is working properly. However, today when starting the bike, the problem was still there. What is strange is that the bike atarts and idles fairly well. The problem occurs when throttle is jerked and it seems to flood the system with fuel as it chockes out and "shoots" in the exhaust. The same happends if i put load on the system with starting to drive, even when working the clutch and thottle in order not to kill it. It is as if the cold start program is not working properly.
If you are sure that the idle control valve is working as it should the you will have to look elsewhere. Other possible causes could be the engine temperature sensor, the air temperature sensor or the MAP sensor or possibly a faulty TPS. A diagnostic check is the only way to determine for sure.
