PO401 error code question

Hello aaf group,
I have a 2002 Explorer with check engine light coming on. My local mechanic tells me that the Code is PO401. The nearest Ford dealership is
about 50 miles away. My mechanic says that there is a list of stuff it could be but he dosen't know which item is the problem. Can anyone tell me what the problem may be or the most likely it could be?
Thanks group , Ed
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P0401= Exhaust Gas Recirculation insufficient flow detected.
No one can tell you what the problem is until the code is diagnosed properly.
It could be a faulty EGR valve. It could be a faulty sensor. it could be a burned hose to the sensor. It could be a vacuum leak. It could be a faulty solenoid. It could be clogged passages. it could be a wiring harness problem. It could be a PCM problem. it could be a programming problem.
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This is "usually" the DPFE sensor... In 2004, Ford issuesd a TSB outlining a "streamlined" diagnostic procedure (TSB 04-11-01)... basically, the sensor would be replaced and, if the code returned, we would then do normal diagnostics.....
HTH

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Ditto the DPFE sensor as the likely culprit. I suggest replacing the hoses too, if your parts store has 'em; they can get clogged and brittle over time.
--Don.
On Sun, 16 Mar 2008 18:43:29 GMT, "Jim Warman"

Radar Tech & Smilin' Commercial Pilot Guy Glider & CFI wannabe kj5kb-at-hotmail.com
"I have slipped the surly bonds of earth; now if I can just land without bending the gear..." "Watch out for those doves...<smack-smack-smack-smack...>"
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