1401 is the code I'm getting on my vehicle, I do not believe it is the EGR valve, the truck is 2001 4.6L.

Thanks in advance

 

P1401 is caused by a bad DPFE sensor.It is located at the end of the rubber hoses that come off the egr tube.

 

the egr valve is most likely not bad. it could be the dpfe. but it is mostlikely the egr tubes are clogged. it is very common on the 4.6 no matter what year.

what grade of gas do you run? do you do atleast one WOT run a week?

 

P1401 - DPF EGR Sensor Circuit High Voltage Detected The EGR monitor checks the DPF EGR sensor signal to the PCM for high voltage. The test fails when the average voltage to the PCM goes to a voltage greater than the maximum calibrated value.

A DPF EGR PID reading greater than 4.5 volts with the key ON and engine OFF or running, indicates a hard fault. Plugged ports won't cause DPFE voltage to go to high.

 

It is necessery to distinguish between the P0401 and the P1401 codes. Stan exp[lained the P1401 very well.

As far as quickly jumping to the conclusion that plugged EGR ports will cause the P0401 code, this is also a mistake. A simple diagnostic will split the EGR
SYSTEM somewhat in half and will lead to a better diagnosis.

Just apply vacuum to the EGR valve while the engine is idling and watch what the engine does.

If it stumbles or dies, the EGR ports are clear and the EGR valve is fine. The problem is either in the DPFE/sampling hoses or the control side of the circuit (EVR/PCM/hoses).

If there was no change, then either the EGR ports are clogged or the EGR valve is inoperative.

See? Cuts out the guesswork!

The grade of gas is irrelevant. Running the engine to WOT is likewise.

Steve

 

I attached a piece of hose to the green line leading to the egr valve. with the engine ideling pulled a slight vaccum the engine almost died, This eliminates the EGR valve and hose correct? Is the only thing left the black unit that the green vaccum hose attaches to? Is this the Sensor? What is WOT?

 

Saying that if you pull vacuum on the egr valve and the engine stumbles eliminates the associated egr tubes is a little flawed. what if they are only partially clogged? the engine will still stumble. what i am saying is it doesn't eliminate the need to clean the egr system.

I miss read the code in the post. I was indeed answering to p0401. sorry.

I personally believe that the grade of gas has a lot to do with it. I have seen premature carbon build up with consistent use of high test.

Also WOT (wide open throttle) does indeed help. when you run it wide open or close to it the EGR opens wide also and helps keep the tubes clean(er) if you rarely go over, say 3k rpm all the time the EGR flow is very light and can accelerate carbon build up.

 

ericl, the DPFE sensor is located at the end of 2 hoses coming off of the steel egr tube. If you look at the middle numbers on the DPFE sensor they will be 9J460. This is the part you want to replace. WOT= wide open throttle. Under Wot or heavy load the egr is closed(no flow) to increase engine power. So would WOT conditions help with preventing carbon buildup, not likely.I haven't done a type of fuel causing carbon study so I can't comment on that one.

 

had a code of 1401, pulled vaccum directly on the egr valve the truck almost stalled, hooked the vacuum line back on the egr valve and pulled vacuum thru green vacuum hose and the egine almost stalled.

I changed the egr vacuum solenoid, ran 8 oz. of sea foam via booster brake line. had autozone clear my code. ran my truck WOT. hit 100 for about 3 min. the service egine light remained off.

truck was off for four hours started the truck and immediatly got the service egine light, took it to autozone and got the same 1401 code. is there anything upstream of the solenoid that I can check, Autozone is going to replace the egr solenoid as the person there said it has to be bad.

looking for any suggestions.

 

ITS THE DPFE SENSOR. Go to your ford dealer and ask for a DPFE SENSOR, THEN YOU WILL KNOW WHAT THIS CRITTER LOOKS LIKE.You know what the egr valve is .There is a steel tube that goes from egr valve to left exhaust manifold.Off this steel tube run 2 rubber hoses.These hoses connect to the DPFE SENSOR. Didn't you look at the part # DPFE=9J460 EGR SOLENOID=9j459

 

Since the nonsense is currently out voting the correct answer here I will add my vote. Stan in on the mark. It can only be three things. A bad DPFE sensor, bad (shorted) wiring from the DPFE sensor, or a computer on the fritz. Do a visual on the wiring (just spend one minute looking it over), if it looks ok then it needs a DPFE sensor (the computer is fine). Its not a solenoid, its not plugged passages, it doesn't need to be run at WOT, and surely doesn't need SEAFOAM.

Look at this:

"I changed the egr vacuum solenoid, ran 8 oz. of sea foam via booster brake line. had autozone clear my code. ran my truck WOT. hit 100 for about 3 min. the service egine light remained off.

truck was off for four hours started the truck and immediatly got the service egine light, took it to autozone and got the same 1401 code. is there anything upstream of the solenoid that I can check, Autozone is going to replace the egr solenoid as the person there said it has to be bad. "

The advice here and at Autozone is cousting this guy money and time. Sorry you were mislead.

 

adaycj, stan. thank you. Stan I found the sensor. on the left side it appears to have a clip that holds the wiring harness to the hose, is there any special procedure for removing the hoses or are they simply pressed on. I called the local ford dealer and the price of this jewel is $98.00. Do I have a better option? I admire you guys for your knowledge and honesty.

 

Adding to adaycj's and STAN's comments:

The DPFE can be tested using a meter. Just look for the output voltage to vary while vacuum is being applied to the EGR valve. The DC voltage will vary proportionately to the amount of EGR flow which should be proportionate to the amount of vacuum applied. Sorry, don't have my schematics available today to look up wire colors and pinouts.

This can be used as a test for gross failure of the DPFE sensor. It still is possible for the sensor to fail with readings that are skewed.

The two vacuum lines just plug on although they are usually secured with clips on some vehicles. They are usually brittle and are easy to break so don't be alarmed if that happens.

Free advice is often worth what you paid for it. Be cautious of who you listen to.

Steve

 

I am a big fan of proper testing and not just throwing parts at a PCM code.

However you do need to apply some pure common sense here. After being on these boards for years you learn a thing or two. And what I have learned about this year of truck with the 4.6 is that they commonly throw this code and 9.9 times out of 10 it is a bad DPFE. They are a known problem. In addtion this truck/engine combination is famous for clogged EGR ports/tubes not bad EGR valves per se.

So my advice would be to start a new thread on where people have bought new DPFE sensors and how much they have paid for them. So you can find the best price and quality when you purchase your new DPFE. And while you are in there you might as well clean out the EGR ports/tubes and replace the rubber hoses conected to the DPFE. Because it is only a matter of time.

Also when people give you the test procedure on here make sure they tell you what to do next if what you are testing isn't bad. IE: test the DPFE. Then what?

Do searches on this (And others) board and look for consistencies in everyones advice and you will usually get your needed answer. And you will rarely ever get a good fix from someone that claims they have been doing it for 20 years. (IE: seafoam)

As for WOT helping to keep things clean. Yes the EGR valve is closed at absolute WOT However it is NOT closed on the way up to WOT so yes WOT will help keep the egr ports/tubes cleaner. And yes consistant runs to WOT will help keep carbon build up at bay. Have you ever seen a driver punch it to pass someone and a big black cloud of smoke spews out?? If you do one WOT run per week you will never experience that black smoke on a passing run!!

I have many friends that own very busy repair shops and vehicles consistantly run on a higher octane gas than is called for have more carbon build up problems.

These are only my opinions and observations. And yes they are free so please feel free to ignore them. I won't mind!

Peace-

 

I'm also having the P0401 trouble code. Wish I had read these threads first. I took off the EGR valve and hooked my Mighty Vac to it. The valve opened all the way with little vacuum and there was zero leakdown. I pumped it open several times. Operation smooth as silk. I sprayed carb cleaner on top of the valve, and it did not leak down. I then pumped the valve open and the carb cleaner ran out. I'd say it was OK. Put the thing back on and tried the run test. When I applied vacuum to the EGR valve, the motor stumbled but did not die. I never got the motor to die, but it stumbled every time and my motor idles very strong, fast, and smooth having new O2 sensors and spark plugs. Judging by the lack of carbon in the EGR valve, I would say that the throttle body ports are fairly clean. I then deduced that the problem was in the DPFE sensor or EVR solenoid. ALSO, my Haynes manual says that bad connections are the #1 cause of trouble codes, so I treated all electrical connections with Caig Laboratories DeOxit. This is SOP on all electrically operated systems I am troubleshooting. You might as well eliminate that variable right off the bat. I then started the engine and let it warm up. I rigged an extension hose to the green tube and touched it to my tongue since I could not feel vacuum changes on my finger. There were vacuum pressure changes as I blipped the throttle, so I figure the EVR solenoid is working. Since the vacuum changes were very weak, I am at this point thinking it is about a 99% probability the DPFE sensor is sending out a signal that is too low and causing low vacuum signals to the EGR valve. After all, P0401 is "flow insufficient", not "no flow" trouble code. I have also been bothered by pinging lately, and insufficient exhaust gas feedback is a cause for that.

I would like to know where to hook my voltmeter to the DPFE sensor terminals, numbering from the top to bottom. Of course, I will attempt to do an online search, but it might take quite a bit of time. I do NOT want to pay $98 + tax for that plastic thing, and I will attempt a teardown and repair before that happens. If I can get a reliable repair, maybe I can offer repairs on these at a much better price than buying new. Your truck will run without that DPFE sensor for a while, so you might want to tear it apart and take a look as to how it works. You probably enjoyed tearing things apart as a kid to see how they worked, and probably never got a lot of those things back together, so no need to let a little age stop the fun.