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Trans wont upshift


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Yesterday we lost engine power by check engine light and hest light blinking. Engine berated down to 10mph. Found shop and they did a forced regen and all seemed good. Started out to get on fwy and trans will not upshift. I tried to manually shift and trans started to upshift but then regressed back down. 
Any ideas? 
Waiting for same shop to open and limp back.

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10 minutes ago, philcarrell said:

Did they check your fuel filters

Not yet. It shifts all 6 going downhill and going up hill down to first. Engine in neutral sitting and driving max’s out at 1500 rpm.

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8 minutes ago, Onthego said:

Maybe the shop didn’t get wires connection plugged back correctly if they took any apart. Hopefully it human error.

 

Well it started doing that issue when the engine and hest light came on. I drove 25 mi doing 10 mph to get to the shop. Ended up having to do forced regen and then the codes cleared. No Allison codes via their diagnosis so far.

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I had an issue with transmission shifting and it turned out to be my pigtail cable to my toad had a short. I only though to unplug it because a friend had the same issue with his auto shift transmission in his Super C when we were on a trip together. His pigtail got caught up in his tow bar a got pinched and cut. 

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4 hours ago, Scott 61 said:

Just curious how many miles do you have on your coach and how do you force the regen do you let your coach idle a lot

My coach has a DPF filter and the first time it did a regen was at 32,000 miles

55k miles, regen about every 100 hrs. 1-2% idle.

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Gary, A DPF regen every 100 engine run hours is very normal for a coach driven at highway speeds and no other issues that would generate soot like a bad injector a clogged egr or bad air flow sensor.  In fact, if the delta pressures across the DPF are not high, a regen will be "normal" and done every 100 hours. 

The Cummins shop should have used the Insite software to view the last 10 DPF regen cycles.  This will tell the technician how the DPF has been functioning in terms of soot loads, regen pressures and temps and whether past regens have all been "normal".  Doing regens sooner than every 100 hours of engine run time, doing regens because of high delta pressures because of soot loading, or doing regens other than normal loadings are all RED FLAGS telling the tech that something else is wrong and needs to be found and fixed.  See if the shop can give you the Cummins Insite printout of the last ten regen cycles stored on your engine ECM.  This will tell you a huge amount of what is going on with the engine DPF.  A copy of your engine ECM history is automatically stored on the shop computer so if they used this software they should be able to print out the DPF regen history report.

One thing folks often don't realize is that when the dash regen light comes on it really means that the operator needs to drive the coach in a manner to do a regen.  It does NOT mean that a regen is actually happening.  To do a regen the coach needs to be driven at 60-65 mph with the jake brake off.  A typical regen takes about 30 minutes.  Regen WILL STOP at idle, when driving below about 30 MPH, when pulling full load grades and when the jakes brake is engaged EVEN THOUGH THE REGEN LIGHT IS ON. 

Monaco did not give us the option to do an idle forced regen.  Because of the high heat generated and without auxiliary fans, to remove heat around the DPF, the fiberglass body could be damaged.  To do a forced regen requires use of the Cummins Insite software and auxiliary cooling fans.

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21 hours ago, Frank McElroy said:

Gary, A DPF regen every 100 engine run hours is very normal for a coach driven at highway speeds and no other issues that would generate soot like a bad injector a clogged egr or bad air flow sensor.  In fact, if the delta pressures across the DPF are not high, a regen will be "normal" and done every 100 hours. 

The Cummins shop should have used the Insite software to view the last 10 DPF regen cycles.  This will tell the technician how the DPF has been functioning in terms of soot loads, regen pressures and temps and whether past regens have all been "normal".  Doing regens sooner than every 100 hours of engine run time, doing regens because of high delta pressures because of soot loading, or doing regens other than normal loadings are all RED FLAGS telling the tech that something else is wrong and needs to be found and fixed.  See if the shop can give you the Cummins Insite printout of the last ten regen cycles stored on your engine ECM.  This will tell you a huge amount of what is going on with the engine DPF.  A copy of your engine ECM history is automatically stored on the shop computer so if they used this software they should be able to print out the DPF regen history report.

One thing folks often don't realize is that when the dash regen light comes on it really means that the operator needs to drive the coach in a manner to do a regen.  It does NOT mean that a regen is actually happening.  To do a regen the coach needs to be driven at 60-65 mph with the jake brake off.  A typical regen takes about 30 minutes.  Regen WILL STOP at idle, when driving below about 30 MPH, when pulling full load grades and when the jakes brake is engaged EVEN THOUGH THE REGEN LIGHT IS ON. 

Monaco did not give us the option to do an idle forced regen.  Because of the high heat generated and without auxiliary fans, to remove heat around the DPF, the fiberglass body could be damaged.  To do a forced regen requires use of the Cummins Insite software and auxiliary cooling fans.

Thanks Frank

As of 4:30pm Friday the techs say they found the problem. VGT and actuator. Ordering parts. Closed over weekend so we are sitting in a motel. Extended warranty says it will be covered. I’ll keep my fingers crossed 🤞 

On 11/20/2020 at 5:59 PM, Chargerman said:

I had an issue with transmission shifting and it turned out to be my pigtail cable to my toad had a short. I only though to unplug it because a friend had the same issue with his auto shift transmission in his Super C when we were on a trip together. His pigtail got caught up in his tow bar a got pinched and cut. 

Wasn’t towing at the time. Techs finally say they found the issue. VGT and acuator. Will see!!!

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9 hours ago, Gary M said:

Thanks Frank

As of 4:30pm Friday the techs say they found the problem. VGT and actuator. Ordering parts. Closed over weekend so we are sitting in a motel. Extended warranty says it will be covered. I’ll keep my fingers crossed 🤞 

Wasn’t towing at the time. Techs finally say they found the issue. VGT and acuator. Will see!!!

Gary, yep, a bad electronic VGT actuator will plug up a DPF with carbon.  In my case I had a hesitation problem after coasting down hill and then there was a power loss when trying to accelerate.  When that happened turbo boost would always drop to zero.  Because no trouble codes were set, I had to use the cummins Insite software in a real time recording mode to sort it out.  Turned out to be a bad electronic turbo actuator.  BTW, these electronic actuators must be calibrated to the engine turbo using the Insite software.  It is not just pull off the old actuator and bolt on a new one.  For a while Cummins stopped selling just the actuator.  You had to purchase both a new turbo with the actuator already installed.  Luckily I was able to find just the electronic actuator without having to buy a new turbo.

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4 hours ago, Frank McElroy said:

Gary, yep, a bad electronic VGT actuator will plug up a DPF with carbon.  In my case I had a hesitation problem after coasting down hill and then there was a power loss when trying to accelerate.  When that happened turbo boost would always drop to zero.  Because no trouble codes were set, I had to use the cummins Insite software in a real time recording mode to sort it out.  Turned out to be a bad electronic turbo actuator.  BTW, these electronic actuators must be calibrated to the engine turbo using the Insite software.  It is not just pull off the old actuator and bolt on a new one.  For a while Cummins stopped selling just the actuator.  You had to purchase both a new turbo with the actuator already installed.  Luckily I was able to find just the electronic actuator without having to buy a new turbo.

Thankyou so much for all your knowledge. I will check Monday to confirm what software they are using. And if I remember right the boss deals with my extended warranty company “Cornerstone” and mentioned replacing whole turbo with actuator. But I will ask Monday.

On 11/20/2020 at 8:52 AM, Onthego said:

Maybe the shop didn’t get wires connection plugged back correctly if they took any apart. Hopefully it human error.

 

Did not take filter apart. Just ran manual regen to hopefully fix the issue.

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11 hours ago, Onthego said:

Found this a good read on understanding VGT (Variable Geometry Turbo) What Fails

https://www.dirtydieselcustom.ca/blogs/cummins/turbo-failure-on-your-6-7l-cummins-here-s-what-you-need-to-know 

Very interesting. Just wish I was more mechanical. I’ve only built two engines in my lifetime with the help of my dad before he passed in 96. The last on was a 57 Mercedes Benz diesel we removed from our 40’ Newporter Ketch that we had planned to sail to Hawaii and back. All mechanical engine, easy peasy!! With help of course.

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On 11/22/2020 at 5:42 AM, Frank McElroy said:

Gary, yep, a bad electronic VGT actuator will plug up a DPF with carbon.  In my case I had a hesitation problem after coasting down hill and then there was a power loss when trying to accelerate.  When that happened turbo boost would always drop to zero.  Because no trouble codes were set, I had to use the cummins Insite software in a real time recording mode to sort it out.  Turned out to be a bad electronic turbo actuator.  BTW, these electronic actuators must be calibrated to the engine turbo using the Insite software.  It is not just pull off the old actuator and bolt on a new one.  For a while Cummins stopped selling just the actuator.  You had to purchase both a new turbo with the actuator already installed.  Luckily I was able to find just the electronic actuator without having to buy a new turbo.

Well its now Wednesday and the VGT actuator was not the only problem apparently. Cummins is conversing with the techs and giving them a list of checks to follow. Left coach behind and rented a second car to grab as much stuff from coach and heading to a family funeral. Will check back with shop next week.

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Just now, Frank McElroy said:

Gary - Very sorry to hear about your loss.  Family always comes first. 

Let me know if they gave you fault code numbers and I can try to help.

Thankyou Frank

Thats been the issue..no codes. And they are using the insite software. Just before I left the shop, all my slides stopped working. Geeze Louise!!!!

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Gary - When I first had my engine hesitation problem after using the Jake brake or coasting down hill and hitting the accelerator, there were no codes.  It drove me nuts.  Yep - really nuts!

So in desperation, I connected the Cummins Insite software to record real time.  Duplicated the hesitation problem and when reviewing the data, I found when I had hesitation, turbo boost always dropped to zero.

Hmm, that's odd.  So, I did some digging and found that Cummins would not set a turbo actuator code unless it failed for more than about 12 seconds.

So, back for another test drive again with Cummins Insite software recording in real time.  This time when I had the hesitation I kept the accelerator pedal floored (I would take my foot off the accelerator when engine hesitated).  Well sure enough the turbo actuator code showed up and yep, the DPF was filling up with soot.  I put in a new Turbo actuator, drove on the highway, to do a DPF regen.  Oh, I also changed the EGR and MAP sensor that was full of carbon but not yet giving a fault code just to be sure.  When you have a failed turbo actuator, it generates lots of soot.  That can cause EGR, MAP sensor, and DPF issues without showing codes.

Another thing to check and I'm sure its on the Cummins check list is to be sure the shop does a cylinder balance test where the engine can run on any two cylinders.  This will identify a bad fuel injector generating soot.

Again - Very sorry for your loss.  Put your family first over this holiday weekend.

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On 11/25/2020 at 8:25 PM, Frank McElroy said:

Gary - When I first had my engine hesitation problem after using the Jake brake or coasting down hill and hitting the accelerator, there were no codes.  It drove me nuts.  Yep - really nuts!

So in desperation, I connected the Cummins Insite software to record real time.  Duplicated the hesitation problem and when reviewing the data, I found when I had hesitation, turbo boost always dropped to zero.

Hmm, that's odd.  So, I did some digging and found that Cummins would not set a turbo actuator code unless it failed for more than about 12 seconds.

So, back for another test drive again with Cummins Insite software recording in real time.  This time when I had the hesitation I kept the accelerator pedal floored (I would take my foot off the accelerator when engine hesitated).  Well sure enough the turbo actuator code showed up and yep, the DPF was filling up with soot.  I put in a new Turbo actuator, drove on the highway, to do a DPF regen.  Oh, I also changed the EGR and MAP sensor that was full of carbon but not yet giving a fault code just to be sure.  When you have a failed turbo actuator, it generates lots of soot.  That can cause EGR, MAP sensor, and DPF issues without showing codes.

Another thing to check and I'm sure its on the Cummins check list is to be sure the shop does a cylinder balance test where the engine can run on any two cylinders.  This will identify a bad fuel injector generating soot.

Again - Very sorry for your loss.  Put your family first over this holiday weekend.

Got a call today my coach is all good. Their explanation is once they reprogrammed and  updated the ECM, all started working great.

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Gary, that's great news.  My guess is that when they were doing all the troubleshooting, or during a software update, an ECM parameter got changed.  Since any time a technician connects to your engine, all old parameters are stored on the Tech's computer, if there was an error made it would be really easy to go back to the original parameter settings.

Keep an eye on how long it takes between DPF regen cycles.  You should get about 100 hours of engine run time (6,000 miles if driving an average of 60 MPH).

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42 minutes ago, Scott 61 said:

I have an 08 Holiday Rambler Endeavor with a 400 horsepower Cummins is there any way to tell how many hours the motor has on it without taking it to Cummings and having them hook it up to a computer thank you

Dont know about where your at but Cummins only wants $95 to run a diagnostics with a printout.

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The silver leaf software I use on my dash computer display reads out total engine miles and hours. And trip engine miles and hours. 

I find this display very helpful in monitoring a number of engine parameters.  The lower right is a real time display of all my tire pressures.

Screenshot_20201201-000049.png

Screenshot_20201130-235650.png

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17 hours ago, Frank McElroy said:

The silver leaf software I use on my dash computer display reads out total engine miles and hours. And trip engine miles and hours. 

I find this display very helpful in monitoring a number of engine parameters.  The lower right is a real time display of all my tire pressures.

Screenshot_20201201-000049.png

Screenshot_20201130-235650.png

Yeah I’ve been hem hawing about buying the Silverleaf. DW is thinking sticks and bricks maybe.

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