QSX cm2250 derating/bad tune

[308smk]

Hello, thanks for having me on the board, I need help.

We bought a tractor last year with the qsx15 cm2250, ESN:79702986, 550/2050.

It's been demandated EGR/SCR by the previous owner. EGR is fully blocked on both exhaust and intake sides. When we got it, it was only blocked on intake side and it would blow the rubber hose off between the EGR cooler and valve.

It sounds rough like a locomotive and rolls coal all the time. Changed the IMAP and a couple other sensors early on.

It threw a 559 code and 1943 air density code. We inspected the high pressure pump and changed it to the newest updated version as it had bad check valves in the pump head. Heard they are a time bomb so just swapped the pump to be safe. No other damage inside the pump on the plungers or cam or tappets/rollers.

We changed the barometric pressure sensor. 1943 code still there and is the only active code.

It is currently jumping between air density limit state derate and normal operation seemingly randomly and turning the turbo red at night. I opened the turbo piping up and inspected the wheels last year when I saw it running red but it all looked really nice.

We are assuming it is a bad tune at this point. We have no idea what's loaded into it or what the motor is set at.

The tractor pulls a big air drill and is usually 65-80% engine load all the time, going higher somewhat frequently.

I have an inline 6 adapter and am trying to track down the usual software.

Any advice or help appreciated.

[tree98]

Your on the right track, get the software and pull a copy of the program for Rawze to have a look at. Chances are it's not gonna be pretty.

[Rawze]

yeah... copy the program from the ecm and e-mail it to me for a proper review of what someone did in there.
info: http://rawze.com/forums/showthread.php?t...5#pid72945

[JimT]

you changed the sensor, but have you inspected the wiring to/from the sensor back to the ECM for damage, corrosion, loose wires, etc...?

You're probably right about a bad delete, but there could still be a separate wiring/electrical issue related to that sensor.

[308smk]

(05-28-2024 )JimT Wrote:  you changed the sensor, but have you inspected the wiring to/from the sensor back to the ECM for damage, corrosion, loose wires, etc...?

You're probably right about a bad delete, but there could still be a separate wiring/electrical issue related to that sensor.

So on this tractor, it's a OEM fitted sensor that they stick into the airbox, behind the secondary air filters. The usual ISX BAP sensor on the wiring harness on the intake manifold doesn't exist on this motor.

We were getting 14.2-14.3psi readings from the ambient air pressure sensor. Elevation is approx 250m above sea level (near Winnipeg) and doesn't change much. So we re assuming the sensor is good although I haven't traced the wiring back. It was running rough and rolling coal before it ever threw that code as well.

I think ive managed to track down what I need to get that file pulled and sent off here soon.

[Rawze]

I was sent the file today...


Its the typical bad delete, just like predicted.

==========

--------
(NO engine operating mode control re-mapping has been done) ...
== Improper engine operating mode control re-mapping (or none at all) is one of the most common issues with bad delete programming. This also causes the biggest problems of all, as the operating mode control logic tree is hard-coded to create as much internal engine friction as it can + choke the exhaust all the time (using the turbo, over-spooling it) to warm up the now missing cans under the truck... but this condition can never be satisfied, causing the engine to perpetually be in this state... eating turbochargers up, beating liners out of the engine block, and all sorts of disastrous results, the severity depending on how hard the engine is worked.

--------
(A whole slew of faults have been blocked from sowing up in the dash) ...
== This is typical of someone who has no idea how to shut things off properly. It is problematic, and it makes it very difficult to troubleshoot real issues because the ecm cannot display half the faults that it is supposed to... fooling everyone into thinking everything is ok.. but it is not.

--------
(EGR gas request and assumption logic is all still in place) ...
No one bothered to correct the injection timing, fuel-air mix, or anything else for the engine to run without harming itself internally without EGR gas. The valve itself may have been disabled, but this has no effect on the ecm's demands or assumptions for EGR on the system. This is harmful and contributes heavily towards progressive damage over time to both the engine and the turbocharger. Another typical bad-delete mistake that is commonly seen.

--------
* All fall-back/auxiliary emissions systems control is still in place. Engine will silent derate and cause injection timing to be all wrong.

* injection timing is significantly too high in all engine modes. This will cause severe damage to the engine over time.

* the fuel-air-mix allowances are set too lean for the power/torque being requested.

== About half of the auxillary/backup/fall-back emissions systems have not been shut off properly. The engine will fight itself, loose efficiency + this will be harmful long term. It trying like h#ell to control emissions of the output to no avail, screwing with injection timing, fuel-air-mix, silent derates, etc,etc.

* NONE of the NOx gas control was shut off or dealt with properly. Again, the engine will fight itself, loose efficiency + this will be harmful long term. It trying like h#ell to control NOx directly by screwing with injection timing, fuel-air-mix, silent derates, etc,etc.

* NONE of the Amonia gas control has been dealt with properly. Again, the engine will fight itself, loose efficiency + this will be harmful long term. It trying like h#ell to control NOx directly by screwing with injection timing, fuel-air-mix, silent derates, etc,etc.

* Injection timing is too high for a de-mandated engine and will eventually eat the valve train out of the engine and/or cause a dropped liner.

* some complete MORON jacked with the engine brake settings, trying to turn them up. THIS IS EXTREMELY DANGEROUS AND CAN CAUSE IT TO DROP A VALVE AND DESTROY THE WHOLE ENGINE WITH ZERO WARNING!.

* The turbocharger has not been re=programmed at all. This will make it over-spool, and over-boost all the time, eventually destroying the turbo and/or causing a cracked piston at some point in its future.

* turbo over-temp control detection was disabled.

*exhaust pressure sensor was partially disabled + someone overrode the entire exhaust pressure sensing, making it impossible for the engine to do cylinder mis-fire detection properly.

* air temp sensing was partially disabled.

* intake oxygen control was partially disabled.

* fuel pressure vs. temps control was partially disabled.

* Someone screwed with air-fuel-ratio limits in the 'scr too hot/ thermal management2' engine operating mode. Looks like someone poking around not knowing what they were adjusting?.

----

Welcome to the bad delete club. Another garbage can delete ...looks just like the typical style of trash programming that is seen by those ill-informed fools that likely hangs out over on those auto-tuning wwwsites. Its an engine and turbo killer for sure.

- Unfortunately, someone also used some garbage Winols, maybe EFI, or some other 3rd party trash software on it, and the file is corrupted. - I cannot fix it as is.

The thing will have to be re-flashed back to its factory settings, etc.. as described in this post here...
ref: http://rawze.com/forums/showthread.php?t...1#pid80171

[308smk]

Update:

So it was the tune. Took a couple days to get all the computer stuff sorted, 10 minutes after I reflashed the factory cal back in and the death rattle went away and the motor smoothed out

Then rawze fixed us right up. We were able to take it out tonight on the land and WOW, he gave us a whole new tractor.

Same field/implement/conditions as before:

-Doesnt smoke. At all.
-Way lower engine load, 10 to 15% less.
-Went from 18-20gal/h to 16-18gal/h fuel rate
-RPM holding steady, doesnt lug going through wet spots anymore.
-Turbo no longer bright red, just a slight glow at night under heavy load. Have a pyro kit on the way.
-Max boost we saw was 33psi at 89% engine load, avg 26-31.
-Significantly smoother running engine especially at idle.

Last Friday we were having SO much trouble with the engine, derating, shutting down. I actually bought a vgt delete kit and turbo, fully intending to just make it "simple", like our old n14s and cm570s. I assumed the tune didn't know how to run the VGT properly, or that the actuator was sticking open and that was the cause of our overboost/derating issues. Then I spent the weekend reading this site and it all made sense. I didn't go to pick up that kit and I got my money back.

Rawze, thank you for all your help and sharing your knowledge. You sorted us out so fast(literally overnight) and spent 40 minutes to go over everything with me. That tractor would have been sitting for weeks without you. Truly appreciated and if you're ever up here north of Winnipeg, come for supper and stay over.

[308smk]

For entertainment purposes, this is what it was like before.

https://youtube.com/shorts/RbpD16rbW9g?s...HXHesNChTP

[Rawze]

(06-02-2024 )308smk Wrote:  ... if you're ever up here north of Winnipeg, come for supper and stay over.

Thanks for the feedback.

Winnipeg??? -- Years ago, I used to go there a LOT (work related). The city center area used to be absolutely beautiful in the winter time. Here is a photo that I took from back in 2001...