The Kioti Rep from down South did call my house yesterday while I was at work and said that they have not heard of an issue like this. The gentleman left his number and said to call him if I had any other questions. He also said to try the filters and call the dealer if it didn't work. I already knew my filters were fine as it ReGens at 2600 rpm's. Today I emailed my local dealer and he called me right back. He also said that I may have a blocked fuel line and that he has seen this happen twice this year already. I told him about the 2600 rpm's while on ReGen and he said "Oh". He said check the lines anyway, the air and fuel filter also. So I did all that and a lot more. I took out the MAF sensor and sprayed it with MAF spray, took every single terminal apart that I could reach. Checked all the fuses and checked all bolts on the exhaust, turbo and any other fitting or place where I could get a wrench on. I fired the tractor up to see it running fine for 3 minutes. It then went back into the 2000 rpm stage. I ran another ReGen on it and that didn't help. So I went in an ate lunch. I came back out and chipped brush for about 30 minutes at 2000 rpm's. I figured that I would take down another Ash tree near the road. I took the chipper off and installed the logging winch. When I started up the tractor it was back to normal once again. I pulled the Ash tree down after notching it and putting in a back cut. I then swapped out the winch for the chipper and chipped up all the tree branches without any issues running at 2500 rpm's. I drove it back to the house at WOT with no issues and parked it. I have no idea what is going on and neither does the dealer. He did say bring it by and they can read the codes. That is an hour away and I will have to find a trailer to do that. In the meantime I will keep using it if it keeps running like it is now.
NX4510 HST RPM's Dropping CEL light
- Thread starter JimR
- Start date
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The Kioti Rep from down South did call my house yesterday while I was at work and said that they have not heard of an issue like this. The gentleman left his number and said to call him if I had any other questions. He also said to try the filters and call the dealer if it didn't work. I already knew my filters were fine as it ReGens at 2600 rpm's. Today I emailed my local dealer and he called me right back. He also said that I may have a blocked fuel line and that he has seen this happen twice this year already. I told him about the 2600 rpm's while on ReGen and he said "Oh". He said check the lines anyway, the air and fuel filter also. So I did all that and a lot more. I took out the MAF sensor and sprayed it with MAF spray, took every single terminal apart that I could reach. Checked all the fuses and checked all bolts on the exhaust, turbo and any other fitting or place where I could get a wrench on. I fired the tractor up to see it running fine for 3 minutes. It then went back into the 2000 rpm stage. I ran another ReGen on it and that didn't help. So I went in an ate lunch. I came back out and chipped brush for about 30 minutes at 2000 rpm's. I figured that I would take down another Ash tree near the road. I took the chipper off and installed the logging winch. When I started up the tractor it was back to normal once again. I pulled the Ash tree down after notching it and putting in a back cut. I then swapped out the winch for the chipper and chipped up all the tree branches without any issues running at 2500 rpm's. I drove it back to the house at WOT with no issues and parked it. I have no idea what is going on and neither does the dealer. He did say bring it by and they can read the codes. That is an hour away and I will have to find a trailer to do that. In the meantime I will keep using it if it keeps running like it is now.
YLee Kioti
Platinum Member
No doubt can be frustrating when no smoking gun is found. Yet after manipulating so many components it is hard to determine what small component corrected this.
Thanks for keeping us updated. Glad it is at least performing correctly for you right now.
Especially with weather cooling off enough to get more production done...lol....regards..
Thanks for keeping us updated. Glad it is at least performing correctly for you right now.
Especially with weather cooling off enough to get more production done...lol....regards..
After doing all the try to fix it things it still wouldn't go up over 2000 rpm's. It did run right when I put my logging winch back on yesterday. This morning it was running fine once again while I moved the logs to my wood pile. I'm hoping that it stays this way. I would also like to know what the problem was.
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YLee Kioti
Platinum Member
Looking back no one has mentioned quality of fuel.
Is it possible that the fuel may have some contamination settled in the tank that possibly loosens up on occasion?
Yup totally grasping at straws.....
Is it possible that the fuel may have some contamination settled in the tank that possibly loosens up on occasion?
Yup totally grasping at straws.....
I did have the fuel mentioned to me yesterday by the dealer. The problem is not fuel quality because under the ReGen cycle the tractor will run at 2600 rpm's for 20 - 30 minutes. This afternoon I used the tractor for another 2 hours running it at 2500 rpm's. I was just playing around and took a run around the property doing some chores and down to a neighbor's house 1/4 mile away. It ran fine with no issues. I'm stumped. Yesterday I did pull the exhaust sensor from the inlet end of the catalytic converter and cleaned it. It was dirty with some black crud accumulation on it. Even after that I couldn't get the motor over 2000 rpm's. Maybe it fixed itself. I now have 4 hours running time with no problems.
CMV
Platinum Member
How does it run the chipper without your butt in the seat? Just wondering since I don't think I can do anything to mine to make it turn the pto shaft if it doesn't sense someone in the seat? I could be wrong and there is a setting for that so people can run wood splitters, chippers, generators, etc. But wondering if whatever you may have done to bypass seat safety interlock is interfering with some other electronic? Grasping too.....intermittent like that, but seems to be fine when "the computer is in full control" points to some sort of sensor. Coming & going as you describe also suggests it's a loose or corroded connection or damaged sensor. Just seems strange that it idles itself down even with hand throttle set and that extinguishes the CEL - you would think if hand throttle was set at say 80%, but ECM makes it lower to say 60% - it would still detect that disconnect. ECM has to be overriding the mechanical throttle position so would think CEL or some other form of error code would be present.
Hope your problem is gone for good.....barring that, hope you find the culprit just to satisfy everyone's (and your own) curiosity!
Hope your problem is gone for good.....barring that, hope you find the culprit just to satisfy everyone's (and your own) curiosity!
All one needs to do is jump the seat switch to use a chipper or any other hand fed attachment. It also makes life easy if you need to stop and start the tractor from the ground for whatever reason. I saw no corroded or burned connections anywhere on the tractor when I pulled them all apart. All of them were plugged all the way in and no pins where pushed out. Today I was moving wood chip piles, firewood and grading where I ground down some stumps yesterday. I put 5 hours on the tractor today and it ran awesome all day.
AWSubie
Platinum Member
JimR - I hope your tractor continues to run well. Since the engine is able to accomplish a regeneration I don't believe your problem is engine related. I think you may have an intermittent fault with the Hand Acceleration Position Sensor (also known as Hand Throttle Lever Sensor, also known as Throttle Position Sensor). There are two Throttle Position Sensors on the Kioti NX, one for the foot pedal and one for the hand lever. Because you were chipping at the time I think the hand throttle position sensor is the culprit. Within the throttle position sensor are two potentiometers. When you move the throttle, the potentiometers send electrical signals to the ECU requesting power. If the signals from the two potentiometers do not match within 15% the ECU will illuminate the Check Engine Light and limit engine RPM between 1800-2000 RPM. If the ECU determines both potentiometers to have failed, the ECU will limit the engine to "limp-home" mode which is 1300-1400 RPM. If the problem occurs again, wiggle the connector on the sensor and see if the problem resolves (you'll have to pull the plastic cover off to reach the sensor).
YLee Kioti
Platinum Member
@AWSubie
thanks for the explanation on the two pots running the engine management system.
I've gotten into the habit of having linked control engaged all the time and never give it a thought.
Though when working, RPMS are typically up around 2k to 2.3k.
Looks like I may have to invest into a shop manual like I did with the CK.
thanks for the explanation on the two pots running the engine management system.
I've gotten into the habit of having linked control engaged all the time and never give it a thought.
Though when working, RPMS are typically up around 2k to 2.3k.
Looks like I may have to invest into a shop manual like I did with the CK.
Thanks for that information. I don't think that is the problem as the tractor has been running great ever since I cleaned the MAF sensor and the soot off of the front muffle sensor (whatever it is). I have put 16 hours on it doing everything that I can think of and it is running great again. I'm leaning towards the sooty front muffler sensor as the culprit. When it would go into limp mode it would drop right down to an idle. From there I could bring the lever back and it would go only up to 2000 rpm's, unless I ran the regen cycle. The regen bypassed all other controls I'm assuming.
