I can't seem to get a DPFE to last for a year or more. For the last three years, about this time of the year my 1999 Econoline 4.6 starts showing a P0402. I clear it and wait for it to happen again, which it does so I clear it again. As time goes on, it fails more and more often.

Along about April, I have to get it inspected, including an emissions test. I go through the diagnostic charts in the manual and conclude that a new DPFE is needed. I pick up a DPFE are Autozone or Advance Auto and install it. Everything is fine for 6,7, 8 months then P0402s again.

The DPFE is warranted for a year but last year I couldn't find the receipt. Anyway, I don't know if it is the DPFE or something else that is causing the DPFE to fail. This year I have the receipt but I don't feel right getting a free replacement if it is really something in the vehicle that is causing the problem.

So my question is, what could be wrong that causes a DPFE to fail after many months?

I have considered that perhaps the hoses dry out or the electrical connector is making poor contact. I have pulled these off, did a visual check, and reinstalled them. Like I am sort of simulating the process of replacing a DPFE. The P0402s keep happening. Then I replace the DPFE and no problems for months.



Thanks In Advance,

Pete

 

Ford Motor updated those - BUT, you have to purchase from the dealership. NO third party vendors will have the updated DPFE Sensor. That's just the way it is and has been for about 6 months or so..

Third party DPFE Sensor's fail prematurely.

 

Pete!

Yer in good hands .... Dr. DPFE is in the house!


MGD

 

Yea , I've done a little DPFE surgery .. In the past..




But I sucked at it

Why must I always tear sh^t apart?? - To see what's inside of course....

Just buy a new one @ your local dealership

 

Have you looked at the discription of the 402 code?
It's excessive flow detected.
Have you looked at the tube from the manifold to the EGR for rust thru, cracks etc.?
Have you tested the EGR for sealing and unreliable operation? use hand pump and observe reaction.
Have you checked for the EGR regulator not closing fully? use vacuum gauge.
These all would be in the direction of an excessive flow fault.
The exhaust is full of moisture and carbon, corrodes and blocks lines and parts.
My first DPFE replacement was 3 years ago at 55k miles. Now have 92k miles.

 

I doubt he has any of those faults - it wouldn't last 3 drivecycles without kicking a code. He says they last him about a year..

 

I had the same problem with sensors from Autozone. I tried two that lasted 3-4 months each. I got my money back and went to the dealer. No problem since.

 

Stop using those junk lowball aftermarket sensors for starters.

 

You and me both. I tore the first one apart also. I always do. I think I am hoping I can find just exactly what the problem is down inside and fix that. You would be supprised how often the actual problem is very simple. I had an EGR for an Isuzu Trooper that kept failing. The actual problem was a conductor that had been scraped off a ceramic substrate. I used a silver circuit pen from Radio Shack to redraw the trace. I had to do it every two years or so. During that time the ERG dropped in price from over $600 to about $100. I sold the truck and handed the new owner back $100 of his money and told him where to get a new EGR.

jbrew, I'm sure your analysis is the right one. I'll go with a dealer's DPFE.

Thanks everyone,

Pete