what is it and where is it on a 4.6L and how much does one cost?

 

The dpfe measures the amount of egr flow. If you remove the plastic throttle body cover, it is the silver sensor about 1.5 inches by three inches with two hoses on the bottom of it just to the driver's side of the throttle body. Ford has changed the style of this several times, so if you get one from the dealer, it probably won't look like the one that came off it. I think they retail for less than 60 bucks at the dealer. Just make sure you hook up the hoses right. One is slightly larger than the other.

Robbie

 

If you remove the plastic 4.6L Triton cover, it is located on the right hand side as you're facing the engine. It's between a Vacuum regulator and the EGR valve.

The style has varied from year to year, and don't be surprised if you have to do some minor tweeking to the bracket where it attaches. Be careful when reattaching the two hoses. One is bigger than the other and the bigger one may not be on the same side as the old DPFE sensor. The small hose will fit on the big input with no problem, so it's common to get them switched.

Suggested retail at the Ford dealer is $86.11, but you can find them from on-line Ford parts dealers for about $64.

 

If you have plans on replacing a dpfe due to codes only,
look further.. Pull the vacuum line off the egr valve and pull a vacuum on it.. if it holds, then your egr ports are clogged up as well. It is hard to say if the dpfe sensor is bad by a code alone.
Sometimes it is and sometimes its sensor and ports.
Good luck

FordMasterTech