EGR Valve control out of calibration?

[darnold9999]

Originally Posted by Kahoona

Back on the road again. Running 65mph on flattish roads with some stops. Running for an hour or so and the CEL just came on and does not clear. I hope it will clear as yours did.

I do want to ask how you were able to tell you had a bad sensor. I would get another if I could tell that.

How did you clean your sensor?
There is a hissing sound coming from the engine which I don't remember hearing before. It happens on acceleration from a complete stop and does not happen when over 45 or 50mph.

This was last December so I can't remember the specific code, but it pointed to the sensor as the issue rather than the valve itself. I seem to recall that it was a calibration error being reported by the ECM for the EGR sensor, but I can't be sure. As I understand it the ECM does a calibration test on the sensor when the engine is started. If voltage is not within a specific range you get the calibration error.

One additional thing I did was to remove the ground from the ECM, clean it and reinstall. I seem to recall I did that first and it also had no impact on the stationary engine so I moved on to testing the voltage on the sensor coming in and going out. I found the testing values online somewhere (just looked on my computer - I did not save the document). The voltage going in was correct, the voltage out was out of range. At this point I cleaned the contacts on the electrical connection to the EGR sensor and then the sensor itself. I did not retest the voltage after cleaning and reinstalling. As I was still getting the CEL light and the same codes I just ordered a new sensor.

I have had a fair number of ground issues with this coach. It sat unused for most of its life about 20 miles from salt water and is currently parked within sight of salt water so corrosion is an issue. I have R&R'd and cleaned most of the ground connections in the coach.

I used carb cleaner to clean the sensor. Sprayed it in let it soak for an hour or so and then repeat then reinstall.

Good luck with all of this - on the last trip it took me almost a month the finally get the CEL codes all cleared. Almost everything was electrical ground issues. The previous virtually identical trip had no issues at all???

[Kahoona]

Originally Posted by hayward3411

So after a few years fooling with the EGR valve (finally replacing it with a new one), cleaning sensors etc I pulled the Turbo off. The Turbo was locked up so I ordered a rebuilt one from River City Turbo, Inc. Very knowledgeable folks and matched up the correct Turbo using engine serial number. I installed the new Turbo a few weeks ago and drove my coach on a couple short trips, wow what a difference. I will be going an a 1,000 mile trip in 2 weeks so that will test it out. No check engine lights........ I did have the EGR valve "out of calibration" code....stop engine code...and a couple others. Most of the time if I shut engine off and restarted it would clear the codes........Good luck

I am showing boost though I haven't paid any attention to how much it does respond so I am hoping I don't have a bad turbo. I will pay attention to the boost levels and check it if I need to. Only the one CEL code for the EGR so far.

[Kahoona]

Spent a lot of time going through the Quickserv


https://quickserve.cummins.com/qs3/p...al/en/4021570/


There is a ton of information there bit nothing on how to test either of the parts I may need to replace. I did learn that clearing the small passages is critical so I will have another shot at that. It still does not tell me how to diagnose the sensor or motor (which is a DC motor, not a solenoid,) and thus harder to test for me.



Interesting info for the next guy: Here is what the engine control computer sees. Every time the ignition is turned on it checks the position of the piston in the EGR body. If it is not closed it throws the code and shuts off the EGR. the CEL remains on until the next time the ignition is cycled. It also checks periodically while in use and if the piston is not closed it shuts the EGR off (as when we are driving). WHen the piston closes it will reset.



To me this says that since mine comes on while driving it could be motor, main body or sensor. Whatever keeps it open. I have cleaned up the body so it has to be one of the others. Quickserve did not suggest how to fix or test further.

[Kahoona]

A couple of days ago we replaced the sensor with a new one. We cleaned the passages under the sensor until spray cleaner blew through unimpeded then sucked out any leftover cleaner and debris. I replaced the exhaust gasket, base gaskets were not available at the time. We made sure the valve worked easily when pressed manually and returned freely.
We headed out for our next stop and found that we were still getting CELs for short times. After an hour of driving we noticed reduced power and longer CELs. On one longer climb we lost a lot of power and got a stop engine light. After a short wait we restarted and the light was gone and the engine did a stationary regen. After that we returned to occasional CELs with some power reduction.
Since the problems always start with a "EGR out of calibration" I have to guess that the problem begins with the EGR system which may cause a carbon build up in the muffler/cat converter. The only things left would be the motor that drives the valve and the exhaust cooler being clogged.

If you have any experience with this please let me know.

[mackwrench]

Not sure if your scan tool will show, but can you see live data from sensors? You'll be able to see reference voltage and return voltage from the EGR, EGR position as well as rest of electrotonic control system. Sometimes these systems will get a "progressive" code, that is something else wrong that's causing the DTC. The ECM also gets barometric pressure reading that tell it how much/often to open EGR based on where you are in relation to sea-level....
My WAG is also sounds like a exhaust restriction, or restriction in EGR cooler. Live data will also show you soot level, exhaust temps at SCR, DPF and turbo....unfortunately, it may have to go to Cummins for in-the-weeds data reading

[thegats1]

I really hope you solve this. Saw your other thread regarding a search for a ISB6.7 forum. Hopefully you keep us posted here. I've learned a lot from this thread this morning. I have the same engine. Also, I understand trying to do this yourself without paying Cummins. Man they are expensive......good luck! You've gone this far. Hopefully you can wrap it up soon and get back to driving under full power!

[Kahoona]

Originally Posted by mackwrench

Not sure if your scan tool will show, but can you see live data from sensors? You'll be able to see reference voltage and return voltage from the EGR, EGR position as well as rest of electrotonic control system. Sometimes these systems will get a "progressive" code, that is something else wrong that's causing the DTC. The ECM also gets barometric pressure reading that tell it how much/often to open EGR based on where you are in relation to sea-level....
My WAG is also sounds like a exhaust restriction, or restriction in EGR cooler. Live data will also show you soot level, exhaust temps at SCR, DPF and turbo....unfortunately, it may have to go to Cummins for in-the-weeds data reading

Interesting. I have a code reader that will show Live Data. Since it plugs into a socket above the radiator on the rear of the coach I cannot read while moving. What is DTC? I will look for a socket on the dash somewhere in case there is one. That might help.

[Kahoona]

Originally Posted by thegats1

I really hope you solve this. Saw your other thread regarding a search for a ISB6.7 forum. Hopefully you keep us posted here. I've learned a lot from this thread this morning. I have the same engine. Also, I understand trying to do this yourself without paying Cummins. Man they are expensive......good luck! You've gone this far. Hopefully you can wrap it up soon and get back to driving under full power!

Thanks. It isn't jst the expensive but the shotgun approach by which we have been kept waiting until 4:00 on the day we had an 8:00 appointment, then given an estimate that included things we did not even have. Needing to go through the estimate and find the extra thousand in BS just chaps....BTW that was in Vegas. There are good ones.



The next stage would be to take a closer look at the DC motor that drives the valve. It is connected on one end. Now that I know that the EGR tests itself every time at start up and periodically during running to make sure that the valve is closed when it should be I also know that our CEL's happen when running. I get the impression that the checking happens in the body of the DC motor (looks like solenoid). This might just indicate that that motor is failing. I will probably have to buy a new EGR valve because I cannot find just the motor. I fear that if I don't find the problem I might clog the carbon burner on the exhaust permanently.

[Kahoona]

I am traveling and staying close to the Mexican border. There is very little cell coverage here. It can take a while to get the next part. Find a place to do work then report back to you so please do not desert me. I will absolutely tell you what the problem and solution is in the end and I do greatly appreciate the help.

[Kahoona]

Summary of problem and what has been tried. We are full timers and are stopping at parks.





CEL for EGR out of calibration. Shows up several times a day for seconds at first no problem. Expert at a Freightliner place said won't be a problem. Should not need a cleaning for another 1,000 mi.


Cel comes on for longer and more often. Power loss. Carbon burner goes onto regen several times. Checked for code and it was the EGR out of calibration again.


Cleaned the EGR body, sensor and passages under sensor. The plunger mechanism in the EGR body now works easily and does not hang up anywhere.



Driving to next place got CEL and power loss. Had a hard time making it up hills and the carbon cleaner in the exhaust regenerated several times. Main hill was 6% and 2500 ft. Had to stop for a whilewhen engine quit. Restarted and it did a regen. Being at the top of the hill we continuse on the downhill.

Bought a new sensor from Cummins dealer $330.00 and installed Cleaned the passages under the sensor even better with air and carb cleaner before vacuuming out. Could not get the hex plugs in the base, under the sensor, out but figured that if cleaner sprayed out and air blew freely.they were clean Checked for codes. EGR out of calibration.



We again left for the next stop, shorter this time. CEL. The only real hill was 1000 ft. Avoided most power loss by keeping the RPM's up on every hill. Ran fine on straight and level. After we got to the park I checked for codes. I added those at the end of the post. Unable to find much info on them so far.


I am wondering if the DC motor that runs the EGR valve is bad. I did get a page on how it works and it seems that it moves the plunger and tests the position to see that it is closed when it should be. It checks on start up and periodically when running. If it is not closing could that allow exhaust into the intake at the wrong times? Will that reduce power or is the computer doing that? Will I cook the carbon burner of have I done it already?


Coded from after the most recent run. Copied verbatim.



SID 70
Inlet air heater driver #1


SID 0027
FMI=7 Mechanical System not responding or out of


SID 27 Variable geometry Turbo
Acturator #1


SID0070
FMI-0 data valid but above normal operating range most


SID0176
FMI 13 out of calibration
IGR valve mechanisim


I have internet through tomorrow. I will see what I can find. Anything that you can tell me will help.
Thanks

[thegats1]

Based on everything you've done so far, I would change out the EGR valve assembly. My guess is Cummins would do this at this point as well. You've gained a ton of knowledge (I have too thanks to you). I can't recall if you mentioned how much the EGR Valve costs, but it seems you may now be at that point. You've definitely put the effort in on troubleshooting and cleaning and replacing the sensor. If you do, I sure hope that fixes it. Would hate to find out it was something downstream causing this.

[Kahoona]

Originally Posted by thegats1

Based on everything you've done so far, I would change out the EGR valve assembly. My guess is Cummins would do this at this point as well. You've gained a ton of knowledge (I have too thanks to you). I can't recall if you mentioned how much the EGR Valve costs, but it seems you may now be at that point. You've definitely put the effort in on troubleshooting and cleaning and replacing the sensor. If you do, I sure hope that fixes it. Would hate to find out it was something downstream causing this.

Thanks. I think you are right. A new EGR assembly is $1400.00 from Cummins, $1050.00 for a genuine new from a independent seller and a refurbished used from eBay $155.00. We are headed to a CG near Bixbee today and can get mail. I believe I will try the used one since they claim it has had the motor section tested.There is not much left. It has to be either the motor section or something downstream. Taking US 10 today to burn carbon and see what happens. If it throws a carbon buildup symbol I can try a manual regen.
Hate to go under the bed again! There really are monsters under our bed

[basketball]

Check for used EGR valve for Dodge Ram trucks 6.7 engine.
Four screws and motor is off egr valve and re install on your egr valve.
Bought egr valve and cooler for $50.00.
All i wanted was the egr valve complete.

[thegats1]

Wow! $1400 and $1050. That is ridiculous, but not surprised. I would do the same thing you plan to do.