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Jeremy, Certified Truck/Bus Technician
Category: Medium and Heavy Trucks
Satisfied Customers: 3362
Experience:  ASE Med/HD Truck Technician, NATEF Diesel Engines and Electrical/Electronics Technician, EPA 608/609 HVAC Certified, Steering/Suspension and ABS/Brakes Technician
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I have an 07 freight liner with Detroit 60 series VI with an

Customer Question

i have an 07 freight liner with Detroit 60 series VI with an intermittent code 39 vanes not responding. while unit is cool it operates as it is suppose to ,but when at operating temp unit goes into a derate type mode and only allows 3lbs of boost pressure
and egr stays at 11%. this only happens when egr temp reaches 200+ degrees. after egr temp decreases to under 135 degrees and let off throttle egr will start fluctuating its percentage. we received this unit from another shop that shop has installed a turbo,
egr,egr pressure sensor,ecm, and a vpod. turbo temp sensor and egr temp sensor have been changed also removed and inspected delt p tubes. looking for a very good detroit person to help with this.
Submitted: 1 year ago.
Category: Medium and Heavy Trucks
Expert:  Jeremy replied 1 year ago.

My name is ***** ***** I will assist you.

Can I get the full VIN on thos vehicle? I want to check something in the ddscn system in regards ***** ***** complaint.

Some of the DDEC VI have software revisions due to this and I want ro see if the server is showing whether it was done or not.

How does the actuator respond any other time? If tou put the truck into EGR bypass mode, will it throw a code? To do that, stsrt truck and let idle for a few minutes. Once tou hear the turbo engage and tou get that high pitch sound, sweep accelerator 3 times and the turbo will die out, the vanes will close, and EGR should open fully into EGR bypass test mode. See if you throw a code.

I'm presuming you have the DDDL program. On it, go to the clscreen giving you the detailed gauges. Scroll to the egr. On pwm1 and pwm4, you will see them swap numbers. Pwm1 will be at 70 or higher when at idle and then go to near 0. The pwm 4 will be near 0 and the pwm 1 will go up to 70 or higher.

Omce you are there and in bypass mode, look at tour Delta P counts and the Delta P pressure. Does it show the counts above 100? If so, what are they? On the pressure, what is it?

This will help me know if the software is off or if the Delta P needs to be calibrated and is causing the issue you are having. Plus it helps to determine if EGR tubes are blocked with soot.

Check the air line going to the VPod for proper air. Also check the air drier. If the air gets hot and creates too much moiture in the line, or is slinging oil, it will flow more when engine is hot giving weak air to the VPod causing this issue.

Immediate things to check are software revision, Delta P counts for calibration issue, air to VPod, also the oil line going to the EGR. If that valve block on the engine is trashed up, it will create issues on the EGR.

One other thing to check is that harness on the back of the engine. It has created a lot of headaches. If the insulatiin feels hard and stiff, it can create havoc when engine gets hot casmusing similar issues. I tend to get codes for the VPod when that happens.

Omce I get the VIN, I can pull full sheet for the 39 flash code as well.

Customer: replied 1 year ago.
Customer: replied 1 year ago.
set into bypass mode delta p count 177 pressure 25.5 egr temp 109. pwm 4= 76 pwm 1 = 0
Expert:  Jeremy replied 1 year ago.

Your delta p count is way high!!!

Those counts should be between 86 and 118.


Check the tubes for blockages or crushing. Then check the Baro sensor to make sure you are getting readings on it. If it is good, then calibrate the Delta P sensor (since it is new) and then run the engine for a test drive.

There is a calibration in the tolls area same as you would do with the Injector cut out. I can;t think on the top of my mind on how to get directly to it, but it is a feature. With the counts being way off, it will make the EGR act all weaird and give you the condition you have described.

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Customer: replied 1 year ago.
attached is a photo of when the truck has boost when it doesnt the egr stays at 11% and delta count is at 103 and delta pressure is at 0.3. i tried to re program the delta p but the selection is not avalible on our dddl program. egr tubes are in good shape and are clear not clogged.
Expert:  Jeremy replied 1 year ago.

Everything looks good, except the Delta P counts.

Remove the baro sensor and clean it off. See if there is any soot on it that would be throwing the numbers haywire. The Delta P relies a bit on the barometer sensor and I am wondering if the Baro might be acting up, causing the programming to act up.

Otherwise, the rest of those numbers looked good...

You knw there is no where on DDSCN about how to do the Delta P calibrate? It doesn't even have the calibrate info for the turbo. The Detroit site can be aggravating! I was trying to find the calibration steps on the site and I am not having any luck with it.

On your DDDL program, do you know what your "write" level is by chance? Is it 1, 2, or 3?

I have 3 and I can get it to come up. Highlight over the Delta P counts, right click and see if you get the same option as I do where you can auto calibrate the sensor. I'm using DDDL 8.1 which has the DDDL 6.4 for the older Detroit 60 series. I think they are all the same.

Customer: replied 1 year ago.
this is what i get when i try to select reprogram egr dp sensor it is not in bold so i cant select it.
Expert:  Jeremy replied 1 year ago.

Well, crap... That is what you need to be able to get it calibrated so this issue can go away...

What are you using to access? Are you using a laptop with a Nexiq Adapter? or something else?

Expert:  Jeremy replied 1 year ago.

See if you can have your vendor up your write level. Tell them you don;'t need DDDR, you just need the write level on the DDDL program uped so you can do simple repairs. The calibrate really needs to be performed to get those counts down to normal so the EGR will work properly.

Customer: replied 1 year ago.
using toughbook lap top with nexiq adapter with dddl 8.1
Expert:  Jeremy replied 1 year ago.

Same as what I am using, but I have that feature turned on. Your vendor will have to contacted to see why your license will not let you do the calibration. You're not programming, just calibrating so that feature should have been available even on a level 1 write DDDL license.

Customer: replied 1 year ago.

ok i have reprogrammed ecm to high calibration setting and re-calibrated delta p swapped delta p repaired intake air leak. still have high dp count and intermittent derate. inspected wiring on all.