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2022 390 Throttle cuts out Engine still Running

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cel throttle
4K views 27 replies 8 participants last post by  atslizewski 
#1 ·
During my ride home from work today my 2022 Duke 390 with 65 miles on it I was in 4th gear with constant RPM and throttle just stopped responding. Engine remained running and check engine light (CEL) illuminated. After throttle was cut out no throttle input would respond but engine was idling. Turned off bike and restarted with no issue, CEL was still illuminated. Rode a little further and happened again same issue. Was able to reset CEL with 3 on and off with the ignition. Rode bike for about 15 miles with no issue and then suddenly happened again, same scenario. Pulled off to side of the road, cut engine, turned back on and bike started right up. Once again reset CEL and happened again after about 20 minutes of riding. Not sure what to do other than calling dealer to see what they have to say.
 
#3 · (Edited)
This sounds crazzy but it's just a quick check and happened to me (and read it happened to just a few others as well) as i had similar symptoms. Check your spark plug lead and make sure it's clipped on properly and not dangling around, takes only 2 secs to check (just in case).

In my case i had recently changed my spark plug to a NGK iridium one (and in case anyone asks, yes i did put on the silicone/rubber sleave from the old plug onto the new one :) ), went riding first day no problems. 2nd day was out riding on a long trip and on the highway started noticing that the bike sputtered and cut out a couple of times (like a missfire) under high load (more than 130kph) except when i came back down to cruising speed (120 kph) everything was good. I didn't realize it at the time so when i pulled into the gas station and filled up, it had some difficulty to start. Ended up finishing the ride and going back home. Next day i was trying to figure out what was going on and took a look at the spark plug lead and sure it enough, it had popped off and was dangling around! I couldn't beleive that the bike was running kinda smooth like the way it was except under high load on the highway and some difficulty to start.

Anyways after fixing it and now knowing the symptoms went riding again the next day. Mid way during the trip, same symptoms re-appeared. Pulled to a gas station and checked and sure enough the little ******* popped off again! Set it again and rotated the L shapped lead around to where i felt the ignition coil wire naturally rests (i.e. since metals have a form of "memory" and may cause resistance if forced into another shape/orientation).

My theory is: 1) The NGK iridium plug may have some very slight tolerance differences at the connector head vs the OEM Bosch plug. 2) When i reinstalled the lead, i had positioned the L shaped lead straight back (9 o'clock position) as i thought it was kinda funny looking when i first looked at how it was originally placed (originally it was more set like 10-11 o'clock position). 3) Vibrations and some bad road bumps. The perhaps slightly different tolerance of the spark plug head makes it less pressure onto the lead so less clamping force combined with how i had set the lead wire where it was now creating some resistance and wanted to pull itself back to it's "natural" position + the vibrations and harsh road bumps on highway finally did the trick to pop it off.

Sorry for the long post/rant but just wanted to post it here in case it helped anyone with a similar issue!

Now to tackle my magic disappearing coolant when i go for a ride! lol (probably a leaking head gasket, yay lol).
 
#4 ·
Took the bike to the shop this morning. Rode 30 minutes highway and city and no issues. Dealer said they will have do diagnostics and see if code was saved. The CEL was off this morning and stayed off during the ride. Dealer sounded surprised to hear that the throttle wasn’t working but engine was still idling. They believe it may be a software issue but not sure.
 
#5 ·
Got the bike back from dealer and was throttle sensor low voltage. KTM flashed the ECU and all connections were tested and grounds were tested. The dealer didn’t say if anything was found loose or was a loose connection. They said it should be good to go know, so only time will tell.
 
#6 ·
I got same issue, I have KTM duke 390 2021 production 2022 since march, from what I’m reading I have much more experience with this unfortunately. Issue is simple, while riding engine is idling, throttle stops responding and the check engine indicator is turning on. For me it happened few times, after bike sit for day or two, check engine lamp would simply turn off back again and while riding it would happen again. I was in my dealership two times now. As above they stated that it's a voltage changes on throttle sensor. First time, they cleaned all electrical connections just to be sure everything is connected, they gave it back and ask to see if issue still appeared. Funny enough when coming back from dealership to home it happened again. When I got back to dealership they took the bike, did a full diagnostic, reset software and ECU and said that from what they tested, no voltage differences in throttle sensor anymore.


I’ve been riding three days and throttle issue did not repapered for now but last night when I wanted to go for a ride, bike did not respond to start button, I got oil pump noise, relay click noise but shaft did not crank. Killswitch was on, side stand put up, everything was fine, I even was ridding an hour before that. I reset battery and did some tinkering and it finally start. I don’t know if those are related, my dealership say’s that I’m extremely unlucky that I have issues with my KTM all the time and normally they are not causing so many issues.
 
#7 ·
I have only rode the bike home from the dealer and it didn’t happen again. I’m going to ride today so I will post an update. Luckily for me the dealer is in the same town as I am. It’s good (we’ll not good) to hear that this has happened with someone else. I scoured the forums looking for a similar situation. I really hate electrical issues as sometimes they can be difficult to diagnose
 
#10 ·
If low voltage, replace the sensor. A sensor must maintain approx 5V, if the diagnosis throws a low voltage, replace the sensor ASAP. You definitely don't want to ride with a faulty accel sensor.

Good luck.

Cheers!
VJ
 
#11 ·
Dealer checked sensor when at the dealer the first time, checks good. They also checked power supply voltage and connection to ground and all seems to check good. Dealer spoke to KTM North America and they re-flashed the ECU. They stated that if it were to happen again they would need to do adjustments whatever that means. Maybe now since it is back at the dealer for the same thing maybe they will replace the sensor. Bike is only 2 weeks old, had no issues for the first 65 miles, this shouldn't happen to a brand new motorcycle.
 
#12 ·
Shouldn't but in reality this is very common in the modern automotive industry - way too much electronics in any vehicle to hope that every component is going to be right out of the box. Stick a carb on it and delete out all the electronics and electric motors and far less issues will result - of course that won't meet emissions but....
 
#13 ·
I called the dealer and now they say the issue maybe associated with the ABS. I didn’t know the two were connected, but won’t know for sure until Tuesday when they can contact KTM to help find a solution. They may need to update ABS software, that is what the dealer said. I guess all warranty work must be approved by KTM.
 
#14 ·
After having the bike at the dealer all weekend, I finally get a call stating that they need to replace the throttle body. The dealer didn't say why it needed to be replaced just that KTM performed the diagnostics and determined that the throttle body was defective and needed to be replaced to fix the issue. They said the part will take 3 to 5 business days to be received and another day for replacement, so maybe I'll have my bike back by sometime next week. I hope this fixes my issue.
 
#15 ·
Sounds like a crap excuse to me.... unless the servo is not replaceable. Throttle body is merely a mechanical device with a throttle servo, throttle position sensor, and injector attached. Maybe the servo for the throttle by wire was the culprit. Glad my 2016 doesn't have throttle by wire :cool:
 
#16 ·
Yeah, I don’t know about an excuse, but I figured since it’s warranty work and KTM is footing the bill for the price of the throttle body, shipping and to pay the shop labor cost to replace it, they must have at least a good idea of the fix. I honestly assumed they would just say to check all the grounds or connections or something like that before they decided to replace parts. This is my first KTM so I’m still weary of the brand at this point. I’ve had the bike for three weeks and has been in the shop half the time.
 
#17 ·
So the throttle body finally came in on Tuesday and the dealer is still completing the replacement. How long does it take ti swap out the throttle body and what is the scope of the work? It has been at the dealer for 13 days now. Friday will be 4 weeks since I purchased the bike. I hope they get it finished tomorrow and I can get it back and ride this weekend.
 
#21 ·
Well after 200+ miles after throttle body replacement it happened again, so back to the dealer tomorrow. This is a real let down. Not sure what the code but same circumstances, this time slowing down and then back to the throttle and nothing. Bike is still running, just shut off engine and restart and it works again. CEL is on again. Thought it was fixed but I guess not.
 
#22 ·
Dealer checked code, same as before. KTM states they want to replace throttle grip and wiring harness of which both are on back order. May I’ll get the bike back before the warranty runs out in 1 year and 11 months. KTM is really dropping the ball.
 
#26 ·
Can you share the part numbers they replaced?
Update to post. They were able to get a throttle grip and get it replaced. I now have 2200 miles on the bike and all seems well.
I guess they've replaced the Ride by Wire system, the throttle sensor assembly, if I understand what you've meant by throttle grip.

Cheers!
 
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