Code po401

The EGR systems in these cars consist of more than just the valve.I have seen many of the DPF sensors go bad. Without knowing all that has been replaced, you will find a trouble chart for diagnosis of P0401 below as well as an exploded view of the EGR components in case you might have missed something

My MIL light came on so I scaned the engine and the MIL code was P0401. Exhaust Gas Recirculation Flow Insufficient Detected. Does this mean I need to replace the EGR valve?

check/clean/replace DPFEGR sensor Perform this test when instructed by QUICK TEST. This test is only intended to diagnose: Differential Pressure Feedback (DPF) EGR Sensor Faulty EGR Valve EGR Vacuum Regulator (VR) Solenoid Orifice Tube Assembly. See Fig. 75. DPFEGR Sensor Pressure Hoses Vacuum Lines Wiring Harness Circuits (DPFEGR, EVR, EVR PWR, SIG, SIG RTN & VREF) Faulty Powertrain Control Module (PCM) Fig. 75: Identifying DPFEGR System Components Courtesy of FORD MOTOR CO.

Do not mean to butt in but it is always the DPFE sensor. Remove it and take the two hoses off. Tap it on a dry surface where the two hoses attach. If any moisture whatsoever comes out, replace it. Replace the two hoses if you can find them. I replace them all the time on Fords.

2001 Ford Taurus 6 cyl Front Wheel Drive Automatic 73800 miles

My MIL light came on so I scaned the engine and the MIL code was P0401. Exhaust Gas Recirculation Flow Insufficient Detected. Does this mean I need to replace the EGR valve?[/quote:d4d8c612d9] Dave you were right on about the DPFEGR sensor. I replaced it and cleared the MIL code. After driving all day the light never came back on. Rescaned the engine and the system monitors checked off the EGR. I would recommend this site to anyone. Saved me a lot of money. Thanks. Hello Jasonray. You can jump in anythime with good advice.

2001 Ford Taurus 3.0L 2V V-6. I reset the check eng light and it stayed off untill I used the cruse. As soos as I put the cruse and the CEL came on and cruse went off and will not come back on. I checked the DTC and it is the P0401 and that is the only code. I am not sure that the cruse going off and the light has anything to do with one or the other. This is from the Freeze Frame: DTC P0401, Fuel Sys 1 Status=Closed Loop, Fuel sys 2 Status=not supported, Calculated LOAd Value=72.55%, Engine Collant Temperature=197.6 F, Short Term Fuel Trim-Bank 1=-3.13%, Long Term Fuel Trim-Bank 1=-0.78%,
STFT-Bank2=-3.91%, LTFT-Bank 2=0.00, Engine RPM=1402.50 rpm and Vehicle Speed Sensor=40.0 mph.
Thanks for any help.
Brown Boot

That code is usually the dpfe sensor, usually the key word, not always.. the dpfe sensor has a long and storied history of failure.

I replaced the dpfe sensor and reset the code have driven about 150 total with about 10 to 15 starts. The Evaporative Emissions Controls monitor has not ran so irt will not pass the country inspection. Is there some way to made the Ev monitor run? The DTC P0401 has not came back on.

BB

I just replaced the dpfe senser again this is the 2nd time I have replaced it sence 2007 when I posted this. I have two other Taurus and that have over 150,000 miles and have never replace it, this one has only 53,000.

What's up, I'm Jim, I replaced dpfe sensor the code came back on, replaced the egr valve code came back on, the replaced the solenoid and still the code came back on. What else can I do before I actually have to put it in the shop?

check items in ic like vacuum leaks or bad hose, and orfice, as well as for partially blocked egr passages.

If it is a clog how do I clean that?

Just to add to this one most likely the eye port is clogged.Most of the egr ports end right behind the the throttle body and that's where there usually clogged at.You can use a small pick or metal coat hanger and some carbon cleaner to help break it up.

My check engine light has been on for awhile now. First it was throttle position sensor, replaced that after we discovered the throttle body on my car was for a SOHC instead of DOHC. The actual engine is DOHC. Got rid of that code, then it was the mass air sensor, got rid of that code. Now its p0401 and we have cleaned it and replaced the egr, and the check engine light still won't go off. Any suggestions? I am going to have to bring it to the junkyard if there is no other options, and I really hate to do that since I truly love this car.

was the DPFE sensor replaced
very common failure related with that code

Yes, we have replaced the DPFE

This DTC indicates EGR MONITOR failed due to PCM detecting EGR flow while driving is less than desired minimum. Possible causes for this fault are:
Vacuum Supply
EGR Valve Stuck Closed
EGR Valve Leaks Vacuum
EGR Flow Path Restricted
EGRVR Circuit Shorted To PWR
VREF Circuit Open To DPFEGR Sesnor
DPFEGR Sensor Downstream Or Upstream Hoses Disconnected, Reversed Or Restricted
VPWR Circuit Open To EGRVR Solenoid
Damaged EGR Orifice Tube
Faulty EGRVR Solenoid
Faulty PCM

From what I understand, there are many components that could give the P0401 code. Where do I start looking for the problem? What are the least expensive and most likely problems? Pep Boys told me I need a new catalytic converter, but given the code it seems like the problem could be in several places throughout the system. And, the CC is pretty expensive to replace if it's not the problem.

A code P0401 most likely means one or more of the following has happened:

The DPFE (differential pressure feedback EGR) sensor is faulty and needs to be replaced
There is a blockage in the EGR (tube), most likely carbon buildup
The EGR valve is faulty
The EGR valve may not be opening due to a lack of vaccuum
Possible Solutions In fixing this code, it is quite common for people to just replace the EGR valve only to have the OBD code return. The EGR valve is not always the culprit.

Use a vacuum pump and pull the EGR valve open while monitoring engine RPM's & DPFE voltage. There should be a noticable difference in RPM's with the EGR open
Clean out the EGR valve and/or tubing to remove deposits
Check the voltage at the DPFE, compare to specified values (refer to a repair manual for your specific model)
Replace the DPFE sensor (with a good quality / OEM one)
Replace the EGR valve

My check engine light came on. The diagnostic code read P0401. The car runs great on the highway but at 25mph and under there is jerking in the engine. Seems to hesitate a bit. I would like to fix it myself. Do I start with the EGR Valve then work my way to the DPFE Sensor. What do you recommend? Thanks

Clean EGR and its passages
replace DPFE sensor

Have a ford taurus 98 with error code p0401 egr insufficient flow detected already changed egr value,vacuum lines,and vacuum solenoid What can i do ?

Check the passages for carbon buildup that is blocking the flow.

Im tryin to find the (DPFE senser) truble code was p0401 cst I looked in your Auto Term Abbreviations but i did not find it please help

Hi there,

P0401 Exhaust Gas Recirculation Flow Insufficient Detected

Check the EGR valve and its system.

Mark (mhpautos)