Can someone help me with what a P1406 trouble code is? Advanced said it was a Auxiliary Emissions Controls but the guy did not know what that meant.

Truck Info:
F150 2wd
Ex-Cab XLT
4.6L V8

He cleared the code and I have driven about 50miles and it has not come back on. I had been driving on very curvy roads and had to come to a sudden stop on a downhill when the light kicked in. The truck has always had 2 things that have bugged me but never been a problem to justify really looking at that I thought may be contributors
1) slight rough idle, not noticeable unless you are actually driving it and does not idle rough all the time
2) sometimes when I stop at a red light my RPM's dip down from just above 600 down to just below 500 for a second or two and then kick back up to just above 600.

Hopefully this is posted in the right place with enough info, long time looker first time poster.

 

The code definition is:

P1406 - DPF EGR Sensor Downstream Hose Off or Plugged

Check the DPFE sensor and its plumbing for damage or clogs.

Based on the code and your descriptions, I'd be looking for unwanted EGR flow due to carbon deposits keeping the EGR valve from seating in the closed position, EGR valve getting uncommanded vacuum due to a leaky EVR solenoid, or a faulty DPFE sensor.

Given Ford's problems with DPFE sensors including an extension of the warranty on them for certain years, I'd suspect it first. Call your local dealer and ask them what the coverage is for your truck. If you're over 80K miles, don't bother...

If you do decide that the DPFE sensor is the fault, do buy the correct upgraded sensor from Ford.

Steve

 

Thanks Steve! I have been doing some reading on the DPFE sensor and it sounds like the part is not all that expensive ~$75 but if done at a shop cost several hundred dollars. I do not have a service manual but am assuming that it's pretty straight forward if I need to replace it, a couple of hoses to take off unbolt the old and replace with the new one? Or is there some special tool that is required or trick not listed in the service manual?

I just have not had anything go out on my F150, yet, to justify needing the service manual.

My truck has just over 77k miles on it so I'll call the dealership and see if there is any extended warranty for my year/model. Knowing my luck this will be a no.

What would be a good estimate on driving distance if the fail mode should come back: 10, 50, 100 miles? Or would letting it idle for a period of time be more incline to cause the failure to come back? I would rather go ahead and fix it now then it wait to trip the check engine light in another 100miles.

 

Some emissions components may be covered by a 8 year 80K mile, so you might want to check into this.

Ryan

 

Ok I was driving home today and I hit a pretty bad bump and the check engine light tripped again. Took it to get the code read and again P1406. I told the guy that it happened yesterday as well. I mentioned that I been checking online and that I read that this was due to the DPFE sensor, which he called something else, and said yes it needs to be replaced. My throtle bottle plastic cover was on so I could not see exactly what the part looked like as I am assuming that it is under the cover. Anyway bought the part and got home tonight to replace it and after I took off the throttle bottle plastic cover there was nothing under there that looked the same as the part he sold me. I looked all over the engine bay and could not find anything that looks remotely close . So I am thinking that he sold me the wrong part.

Here is a pic of what I think is the DPFE sensor


Here is a pic of what they sold me:


What I did notice is that there are 2 screws right beside what I thought was the DPFE sensor that have nothing on them, see pic


What I thought was odd was that the part they sold me fits on those screws. Here is a pic

 

Ryan, thanks. Yea I never got a chance to call the dealer today and when I was on the way home it tripped again. Since the part was only $40 I figured I would go ahead and replace it on my own, since it didn't seem that difficult. Anyway see post above about problem with the part Autozone sold me.

Will call Ford tomorrow to see if it's still covered.

 

The 8/80 compnents on he F150 are the cats and the PCM. Everything else is 3/36 except for any parts for which Ford has extended the warranty, such as the DPFE for an additional 2/24.

FWIW, can't load any of the photos...

Steve

 

Steve, I have corrected the photos and they should now be viewable, let me know if you still can't bring them up.

Here is a pic of what I think is the DPFE sensor


Here is a pic of what they sold me:


What I did notice is that there are 2 screws right beside what I thought was the DPFE sensor that have nothing on them, see pic


What I thought was odd was that the part they sold me fits on those screws. Here is a pic

 

Yep they sold me the wrong part and I was looking at the wrong part. Got the correct one that matches what mine looks like now. Called Ford and they said that there was an extra warranty on the newer models but not on the 01's

I had disconnected the battery last night before I started, so my check engine light was reset. I have driven about 50miles now and it has not come back on. I did check the hoses on the DPFE sensor (now that I know what it is) and everything looked fine, no cracks in the hoses, hoses were on good and tight, electrical connection looked fine, etc... So I am thinking of driving a while and see if the light comes back or not.

 

I just wanted to post my latest on this. After I drove around for about 430miles with the old sensor (had reset the computer) my check engine light kicked back on, and yep P1406 again. I was acutally driving home from Autozone when it kicked back on, from returning the correct part. They sold me the wrong part at first and when I went to install it I disconnected the battery and that reset the computer. Since it did not kick back on when I first started it I figured I would drive around for awhile to see if the problem was the sensor or that it just gave a bad reading. I figured I had driven far enough that it was not going to come back on, well guess I was wrong. Anyway replaced the sensor, and have been around 900miles or so on the new sensor and it has not tripped the code, so I guess it is fixed.

I also wanted to note that the new sensor has cleared up my rough idle. I do not get the dip in RPM's when I come to a stop anymore.