okay fellas....i did some tests on my dpfe sensor going by this thread http://www.ford-trucks.com/forums/34...fe-sensor.html and I get 1.03 volts on the top wire with KOEO and 5 volts on the bottom wire...when i applied suction with a hose attached to the forward most hole and it changed and went up to about 2.08 no matter how hard i sucked on the hose....two things i noticed are that the suction did not hold my tongue(with or without the back hose connected.) and the back post for the hose seems half the length of the forward one and the hose came off extremely easy...the ID of the hose looks the same as the other one....also, i sprayed for vacuum leaks and found none and I took the top hose off of my egr and applied vacuum and the the engine idle lowered some but not to the point of dieing. So....is my dpfe bad? and should have the egr totally made the truck stall? Heres some pics...

 

That is a pressure sensor by inducing a vacuum to it won't tell you anything, however if you apply vacuum to the egr valve with the engine idling it should have made the engine stall. (Did it hold vacuum or leak down with every squeeze of the vac pump?)

Clean the egr ports they are clogged. I'm not certain if yours is the same as the older 4.6 engines but if it is you will need to remove the throttle body from the manifold because that is where the ports are at that clog up.
maybe someone else can chime in if those ports are still under the throttle body.

 

I don't think it was holding pressure, i used a hose and was sucking on it i don't own a vac pump.....i plan on cleaning my ports and had already tried removing tb but, when i removed a line from the back antifreeze starting shooting out. Here's a pic, maybe you can help me understand these 2 lines on the back of my tb... the one with the square around it is the hose that antifreeze was coming out of when i removed it so i quickly put it back on...I have no coolant in my oil.

 

You need to pull the egr valve to clean the ports. I have a 02 4.6 and that's how to reach them. That hose on the back of the throttle body with the coolant in is for the Pcv valve.

 

Okay, so how do i remove the whole plenum? Do I take the further one to the rear off of the whole unit housing both hoses? This is the only part that confuses me.

 

NO, my egr valve was not holding any vacuum, i checked again and when i suck on the hose that i had attached, the idle really goes low but when i hold my tongue on the end, the idle goes back to normal pretty much right away

 

Hi , i am getting the p0405 code and i think i have it figured out but while i wait for my 2 hoses i will let you know what i did so far , took off throttle body and cleaned it , replaced the vaccum regulator ( mainly because buddy before must of broken part that holds it on and it was bouncing around) , replaced egr valve about 2 months ago after replacing the egr tube , and last i bought a dpfe from auto barn than returned it because i thought it was faulty and a mechanic told me to buy one from dealer instead so i went to put it on and noticed the two hoses that go from dpfe to egr tube do not seem to be the right size, the longer one has a smaller diameter and the shorter hose has a bigger diameter, from what i have figured out it seems that the longer hose should be the bigger diameter and so on for the dpfe to sit on there right. This being said the bigger port on the dpfe has to be forced into the small hose and the small port slides into other hose with ease. I dont understand how this could be, but i looked at several different diagrams and i am sure i have the sensor sitting on the right way with the hi and ref ports where they should be. I ordered the two small hoses at 20 bucks a peice from the dealer so i will find out if i am right in the next two days. Would an air leakage around the dpfe set off the p0405 code, i see so many people get the p0401 code but not alot of p0405 issues. Any help is much appreciated.

 

O and code means something like egr voltage circuit a low, and i heard before they used an aluminum dpfe, could the ports have been opposite and if and when replaced they just used the same hoses. Can anyone verify the sizes of those hoses on their truck, i am so ready to see if those hoses are even going to fix my problem, o and i never mentioned either i have really low idle after truck is warmed up, from cold starts and runs fine once you drive a few miles it goes back to low idle .

 

Ok so just posting follow up in case others run into this issue sometime, i ended up ordering the 2 new hoses from the dealer that go from the egr tube to the dpfe sensor and all seems to be fixed with the low idle, and p0405 code is gone. I think what must have happened is the PO must have changed the hoses at one time but instead of getting the right hoses from the dealer with the proper sizes he cheaped out and used whatever hose he could find, so with the hoses loseing pressure the dpfe must have been sending bad reading to the egr valve causing my low idle and stalling when truck was hot. The hoses were 20 bucks a peice but obviously size and whatever kind of pressure hose it is makes a difference, the hose that was on there was thick with orange on the inside, the new is just straight black. My engine seems to have a little shake when idling now that i never noticed before though , any ideas ? Would a vaccum leak do this?