My daughters 97 4.6 with 135,000 miles pulled a po401 code last night. I was going to check for carbon buildup first and then look at replacing the DPFE. I was wondering if anyone out there has had a similar problem?
<img src="Http://www.scotthansen.net/images/po401dpfe.gif">

 

I had the same code and replaced hose going into tht DPFE, it was cracked

 

Connect a vacuum pump to the EGR valve while the engine is running and pull a vacuum. if the truck bogs out and wants to die, the egr is working fine. if thats the case, examine the hoses to the dpfe sensor and if they look alright, odds are it's the dpfe sensor. known problem with more then just the f-150's.

 

I replaced the DPFE on Saturday. It cost $121 at my friendly Ford dealer. The code came back on Sunday. I guess I'll research the EGR and its piping. The hoses to the DPFE looked good, so i'm assuming it's in the EGR / throttlebody area. Anyone else suffered this?

 

I think you need to pull the throttle body and clean the two ports. Very common for these to clog with carbon.

 

My EGR ports on the upper intake were completely clogged. I was going to replace the DPFE sensor but I dont drive the truck that much and it only has 75000 miles on it.It only took about an hour to completely do the job and it was well worth it. 500 miles later and no more CEL.Everything that I could see in the intake was completely clean and carbon free. Please check these ports prior to spending $100 on a new sensor.

 

I had the same issue,,, I replaced the EGR and the DPFE sensor...
problem solved... My DPFE was'nt $121.00 though...
I think the EGR and the DFPE were about $125.00 together though

try www.rockauto.com for ford parts...you can get these two parts
factory motorcraft for ALOT cheaper than a dealer...
Good luck!

 

Well, Today I pulled what I believe is call the upper intake, and zowie Batman you guys were right. The two little EGR ports where completly clogged with carbon. Cost a few bucks for gaskets and I'm pretty confindent it won't come on again for awhile.

Thanks to all who responded. If I hadn't been lazy I could have saved $126. Atleast I'll know what to expect if I ever get highn mileage on my 01.