Kioti RX6620 check engine light on

Sean2202 · Oct 6, 2021

Greetings,

Check engine light came on today with the Kioti RX6620. Tractor has 140 hrs on it and purchased this past spring. The tractor was running fine then started to spit and sputter and then the light came on. All maintenance has been performed so far according to the dealer handout. Regens have been performed when light comes on. If I disconnect the negative battery terminal the light will go off. If I shut down the tractor and come back 10 mins later the CEL will be off. When the light is off after shutting the tractor down it runs 100% fine for a few minutes. Then it will spit and sputter and the foot throttle or hand throttle does not effect performance when its spitting and sputtering. Then the check engine light will come on and the machine will shut off. After restarting with the CEL on the tractor will only run to 2200 rpm. I tried to do a forced regen when the light was off after I disconnected the negative battery terminal and the regen started, a few minutes later it started spitting and sputtering then the machine went back to idle and the regen stopped. Fuel filter was changed again with no difference. No water in fuel filter. Other diesel equipment is all running fine. No other lights on. Air filter is clean. What could be the cause of this malfunction?

Thanks for any help
Sean

rademamj1 · Oct 7, 2021

My first thoughts are that something is indeed wrong with emissions, and your in limp mode right now. First make sure its not a fuel issue, so troubleshoot the fuel system throughly. Once your happy the CEL is not fuel related, move on to emissions.

Continue trying for a manual regen, and also check your engine codes for possible cause of CEL. Sadly, Kioti does keep many of the engine codes proprietary, requiring a Kioti dealer and his laptop to sort out what exactly is going on. Sometimes its just a faulty emissions pressure sensor causing the CEL and limp mode.

If you get a engine code reading, post it here and some forum members can provide more information.

Update: i read your original post again, and sounds like your confident its not a fuel issue.

IndyJay · Oct 7, 2021

"Tractor has 140 hrs on it and purchased this past spring."

Isn't it still under warranty? How far is the dealer? If not too far they may send someone over with a scan tool to see what is bugging out.
Otherwise you may have to haul it over to them. Perfect case for the recent "Right to Repair" thread on this forum.

rademamj1 · Oct 7, 2021

Give it a few more attempts at regen, and keep the rpm's as high as possible to encourage a regen. Even if its not successful, you now have another item checked and to communicate back to the dealer.

Robin Veerman · Oct 7, 2021

I’m wondering if you’ve contacted your dealer with the same info? It Would be interesting to hear what they might suggest. Even though you probably have warranty contacting your dealer should have been your first priority. The last thing you want to do is follow someone’s misguided suggestion and create a bigger issue. All the Best and Keep us posted, Dutchy

Sean2202 · Oct 7, 2021

Thanks for the replies. Yes we have been in contact with the dealer back and forth before posting here and so far they have been good. They are about 1 hour away. Yes it is under warranty. Hopefully they can come down with a scan tool / laptop, otherwise there is a huge sticker on it that states, "trucking for warranty or service work not covered under warranty."

The dealer first stated that its fuel related, water in fuel. Fuel filter was changed. I used water detecting paste and no water in tank. Also cut open old fuel filter and checked for water, none found and no water light on. All other diesel machines in fleet run fine.

Today I figured what the hell change the oil and filter, Oil had 84 hours since last change. Started up, ran fine, forced regen again. About 10 mins in running at 2600 rpm tractor started to spit and sputter, CEL came on then RPM dropped and tractor shut off.

Tried an automotive OBD tester, tester said it could not connect.

After telling the dealer that I don't believe water is an issue, they said it could also be crank sensor related. Not going to fiddle with that. They need to scan it at this point.

I did read another thread on here that someone had trouble with injector dumping too much fuel in and clogging DPF on this tractor at around the same hours.

One other thing to note is that to me it seems to regen a lot. I have limited experience with tier 4 engines and how much they are supposed to regen. I posted about it on here in another thread. Possibly related?

IndyJay · Oct 7, 2021

There should be a warning light for water in fuel. My DK4510 has one:

Sean2202 · Oct 7, 2021

IndyJay said:
There should be a warning light for water in fuel. My DK4510 has one:

View attachment 715985

Yes my dash has a warning lamp for water in fuel. My dash looks different than above. No warning light for water in fuel was ever on or any other lights on during this process except the CEL. No water found in fuel filter or tank with water detecting paste.

MinnesotaEric · Oct 7, 2021

rademamj1 said:
Sadly, Kioti does keep many of the engine codes proprietary, requiring a Kioti dealer and his laptop to sort out what exactly is going on.

Worse, since Kioti is a small player in the broad diesel industry, universal diesel code readers do not support Kioti. All to say that anytime the "right to work" legislation comes up, vote, "YES!"

I tend to agree with your assessment: something is lying to the ECU that eventually causes the ECU to trip into limp home mode. While not directly related to Sean2202's problem let me tell you a Kioti limp home mode story: In 2014, when I first got my NX, my tractor went into limp home mode because while the ECU claimed it was regenerating (every 8-12 hours), it never got the engine high enough up to temperature to complete a regeneration cycle. As a result, my new 60hp tractor was absolutely gutless. At the time I was super frustrated, and any negative thing said on these forums was ridiculed or deleted. My fix for the poor running condition, as well as the diesel industry fix (because fleets were experiencing the same problem as the limp home problem was a Tier IV spec problem and not just a Kioti problem) was to install a warmer thermostat that allowed the engine to run at a higher minimal engine temperature, one that was warm enough to

1) Stop the engine from continually running on the warm-up fuel map thereby plugging the DPF at a much faster rate, and
2) Also allowing the engine to be warm enough to fully complete a regeneration cycle so the machine wouldn't eventually get tripped into a limp home condition because the DPF was plugged up.

Here is a video of my frustration with my tractor in 2014 before I puzzled out the problem and installed that warmer thermostat.

Also, I should add that if the thermostat has a spring-loaded bypass, then that too can cause the same problem with excessive warm-up times while in use as the coolant can overcome-that weakening spring-loaded bypass and slip right by the thermostat entirely. The condition will act similar to a T-stat being stuck open.