CEL came on. Code P0401(EGR Flow Insufficient) Does anyone know what it means.???

 

1. AIR FILTER RESTRICTION


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NOTE: Repair any other EGR related DTCs before proceeding.
1. Examine the Air Filter minder.


Is the air filter restriction within allowable limits?
Yes

Go To 2

No

Replace the Air Filter.
Perform the POWERTRAIN VERIFICATION TEST - 6.7L. (Refer to 28 - DTC-Based Diagnostics/MODULE, Engine Control (ECM) - Standard Procedure).



2. INTAKE AIR HEATER RESTRICTION


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1. Remove air inlet connection and inspect Intake Air Heater.


Is the Intake Air Heater restricted?
Yes

Clean area and reassemble.
Perform the POWERTRAIN VERIFICATION TEST - 6.7L. (Refer to 28 - DTC-Based Diagnostics/MODULE, Engine Control (ECM) - Standard Procedure).

No

Go To 3



3. EGR SYSTEM LEAK


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1. Look for visible signs (soot streaks) of an external EGR system leak.


Are there any EGR leaks?
Yes

Repair the leak in the EGR system.
Perform the POWERTRAIN VERIFICATION TEST - 6.7L. (Refer to 28 - DTC-Based Diagnostics/MODULE, Engine Control (ECM) - Standard Procedure).

No

Go To 4



4. INTAKE AIR SYSTEM LEAK


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1. Check for leaks in the Intake Air System. Perform the INTAKE AIR SYSTEM PRESSURE TEST. (Refer to 29 - Non-DTC Diagnostics/Drivability - Diesel - Diagnosis and Testing)


Was an Intake Air System leak found?
Yes

Repair the Intake Air System leak.
Perform the POWERTRAIN VERIFICATION TEST - 6.7L. (Refer to 28 - DTC-Based Diagnostics/MODULE, Engine Control (ECM) - Standard Procedure).

No

Go To 5



5. THERMOSTAT OUTLET


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1. Remove the EGR Outlet Temperature Sensor from the thermostat outlet.


Is the outlet free of debris?
Yes

Go To 6

No

Remove debris from outlet.
Perform the POWERTRAIN VERIFICATION TEST - 6.7L. (Refer to 28 - DTC-Based Diagnostics/MODULE, Engine Control (ECM) - Standard Procedure).



6. EGR COOLER LEAK


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1. Verify EGR Cooler is not leaking.
2. Check for coolant in EGR plumbing, engine overheat fault codes, and low coolant level.


Are there signs of an EGR Cooler leak?
Yes

Replace the EGR Cooler.
Perform the POWERTRAIN VERIFICATION TEST - 6.7L. (Refer to 28 - DTC-Based Diagnostics/MODULE, Engine Control (ECM) - Standard Procedure).

No

Go To 7



7. EGR CROSSOVER TUBE RESTRICTION


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1. Remove EGR Crossover tube from EGR Cooler and EGR Valve.
2. Inspect tube for restriction.


Is the EGR crossover tube restricted?
Yes

If possible, clean the tube. If not, replace tube.
Perform the POWERTRAIN VERIFICATION TEST - 6.7L. (Refer to 28 - DTC-Based Diagnostics/MODULE, Engine Control (ECM) - Standard Procedure).

No

Go To 8



8. EGR COOLER FOULING


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1. Remove and clean the EGR Cooler with approved Mopar EGR System cleaner.
2. Reinstall the EGR Cooler.
3. With the scan tool, erase DTCs.
4. Turn the ignition off for 30 seconds.
5. Start the engine. It may be necessary to test drive the vehicle.
6. With the scan tool, check for a one trip fault logged against DTC P0401.


Is there a one trip fault logged against DTC P0401?
Yes

Replace the EGR Cooler.
Perform the POWERTRAIN VERIFICATION TEST - 6.7L. (Refer to 28 - DTC-Based Diagnostics/MODULE, Engine Control (ECM) - Standard Procedure).

No

Test complete.
or just unplug the EGR valve like most do

 

Truck was bought on Nov.14, as of today Dec. 22 it has 9200 plus on the OD. Lot of interstate miles, you'd think that The EGR system would be working properly. With all the problems associated with the emission system I've been waiting for that light to come on,and it did. Take it to the dealer have it cleaned, truck down for couple days????Unplug EGR???

 

thats up to you...but im sure there is ALOT of soot buildup in the egr valve and cooler,the tip of the sensor by the thermostat. if you take it to the dealer expect a 2-3 without the truck. i work on these thangs daily. i see alot of things on these trucks and things that have fallen off and dont say a word to mang. like i said its up to you !!!

 

Appreciated the info. Been reading some other post on here and over on the cummins forum. I'd like to do the cleaning myself,if cleaning is only whats involved. You must be a tech at the dealership.I"d like to leave the truck as stock as possible without deleting or unplugging anything because it's new. I'll leave it like that and do the cleaning as long as it's possible until something happens otherwise.If you are a tech nician would you mind me PM you with certain questions pertaining to the truck????

 

im willing to help as much as possible

 

B). EXHAUST GAS RECIRCULATION (EGR) SYSTEM INSPECTION:
1. Remove and inspect the Exhaust Gas Recirculation (EGR) System.
a. Remove the EGR Crossover tube from the vehicle.
b. Remove the EGR Valve from the vehicle. Disassemble the EGR Valve for cleaning.
c. Remove the EGR Cooler from the vehicle.
2. Thoroughly clean the EGR Crossover tube, EGR Valve, and EGR Cooler in Mopar
EGR System Cleaner.
3. Remove the EGR Temperature Sensor. The sensor is located on the intake
plenum/snorkle, below, and to the rear of the EGR valve.
a. Clean the sensor end of the EGR Temperature Sensor with Mopar Brake Parts
Cleaner.
b. Install the EGR Temperature Sensor to the intake plenum/snorkle

 

Just got through inspecting and trying to clean whatever I could. The EGR valve didn't look that bad. Cleaned whatever I could of the "plunger". The EGR temperature sensor wasn't that bad either,anyway I cleaned it with a Sensor cleaner. The CEL came on Sunday Up in Denver,CO. I didn't want to drive it back to Houston,TX. without checking it out, dealer closed on sunday took it to a Checkers auto parts store and had them look at the code,which was P0401. They "cleared it " and drove back.Fuel mileage when down a little.Question ,will the CEL come on for the same situation.Also looked at the EGR crossover tube and it didn't look that bad so I didn't take apart the EGR cooler.Is that sufficient cleaning???

 

then i would say most of the soot in prob. in the cooler. we have had a few truck here in Ga go out west up in the mountains and come back with ckeck engine lights on STAR which is our tech center says they are seeing more problems out there than any other place.how much soot is on the sensor on the back of the intake tube right behind the egr valve

 

Had to go to work with the truck,and will be doing a local run Christmas Eve. If I can work on it I will try and clean the EGR Cooler Christmas day. The sensor right below the EGR on the intake wasn't that bad anyway I cleaned it with the sensor cleaner. Did you say there was a sensor near the thermostat???Thank you for all the info.

 

Interesting that you jump directly to the EGR without knowing what the CCS readings are, or if there is any signs of oil pullover.....and just MAYBE if you are cleaning the EGR you might want to bench test it while it's off??? Just because it's clean doesn't mean it's good. Looks like to me your fixing the "effect"....not the "cause". I'd love to elaborate, but I no longer throw my info....or chryslers, up on a public bulletin board. Hang around here long enough and you'll see why just like many before you.

 

With 3,262 posts, you've been around the block more than once. I just need answers to simple questions and appreciate any info given.Down time for my truck is not an option .When you start going into CCS readings ,oil pullover and bench testing, that's way over my head.What's a forum for if you can't elaborate???

 

the problem is soot buildup we all no that... and the problem is the EPA. nothing wrong with that engine at all. just all the emission crap that was added thats making my job ALOT harder