NX4510 HST RPM's Dropping CEL light

[YLee Kioti]

"MAF sensor and the soot off of the front muffle sensor"

Well that is some great insight. Mind sharing where they are located. Although it may sound obvious for many; not sure if tractors have the same install as a vehicle.
I would think the MAF sensor would have a body just past the air intake.
As for the muffler sensor guess it would mean either removing the FEL or maybe squeezing under the hood and look for conductors at a muffler flange.
Did you use the auto two pack, which is the MAF and throttle body cleaner combo?

One would think this would be a maintenance item in our owners manual. I can see your frustration because when I'm knee deep in a project and need the machine to support that work it just puts one behind, along with bad weather etc.

Glad to read you're now running strong. Thanks for keeping us updated.

 

[JimR]

"MAF sensor and the soot off of the front muffle sensor"

Well that is some great insight. Mind sharing where they are located. Although it may sound obvious for many; not sure if tractors have the same install as a vehicle.
I would think the MAF sensor would have a body just past the air intake.
As for the muffler sensor guess it would mean either removing the FEL or maybe squeezing under the hood and look for conductors at a muffler flange.
Did you use the auto two pack, which is the MAF and throttle body cleaner combo?



One would think this would be a maintenance item in our owners manual. I can see your frustration because when I'm knee deep in a project and need the machine to support that work it just puts one behind, along with bad weather etc.

Glad to read you're now running strong. Thanks for keeping us updated.

The Mass Air Flow sensor is right behind the radiator on the intake hose between the air filter and intake manifold just like on a car. I used MAF spray cleaner on it. It looked spotless to begin with but that doesn't mean it wasn't dirty up inside. The sooted up sensor is on the inner side of the muffler laying horizontal at the intake end of the muffler. I crawled up in there and took it out. It looks like a mini 02 sensor.

 

[YLee Kioti]

@JimR:

Thanks greatly appreciate it.

When I first bought the CK4010HST I built an Excel spread sheet to match the owners manual than added tabs for parts trailer, vehicles etc.
So I will take you info and add it to the maint. section. Cause if that time ever comes, highly doubt I could ever find this thread again...Ha..
Pretty awesome job there so thanks again and have a pleasant week........

 

[JimR]

@JimR:

Thanks greatly appreciate it.

When I first bought the CK4010HST I built an Excel spread sheet to match the owners manual than added tabs for parts trailer, vehicles etc.
So I will take you info and add it to the maint. section. Cause if that time ever comes, highly doubt I could ever find this thread again...Ha..
Pretty awesome job there so thanks again and have a pleasant week........

Hopefully you or I will aver have to deal with this issue again.

 

[JimR]

Warm it up and manually regenerate it. I think your exhast filter is plugging up your machine. That is what happened to my machine.

Eric, The problem with my tractor is the hand lever accelerator switch is bad.

 

[JimR]

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).

BINGO, you hit the head of the nail with the hammer. I dropped the tractor off last Saturday. He called today to say that the throttle control lever is bad. You called it right. I guess that I should have checked this out the first time around. The wires on it were tight. I never did a meter reading on it. Shame on me. Maybe this went bad from spending its first two years out in the weather at the dealer. How did you know about this control unit?

 

[AWSubie]

Chapter 12 of the Work Shop Manual has a table listing fault codes and symptoms (actions the tractor will employ when fault codes are triggered). Only 9 fault codes will trigger a "limp home" response. Most of these responses have to do with with either the foot pedal sensor (throttle position sensor) or the hand throttle lever sensor. From your description of the problem the most likely scenario was an issue involving the hand throttle lever sensor.

 

[JimR]

Chapter 12 of the Work Shop Manual has a table listing fault codes and symptoms (actions the tractor will employ when fault codes are triggered). Only 9 fault codes will trigger a "limp home" response. Most of these responses have to do with with either the foot pedal sensor (throttle position sensor) or the hand throttle lever sensor. From your description of the problem the most likely scenario was an issue involving the hand throttle lever sensor.

"ONLY" 9 fault codes, OMG. Where did you buy your manual, dealer or direct from Kioti?

 

[AWSubie]

I bought the manual from the Kioti dealer.

 

[JimR]

I bought the manual from the Kioti dealer.

Thanks, I am going to get one of these for future problems. I figured that I wouldn't need one until around 1000 or so hours. LOL