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PO401 EGR flow insufficient

(1999 Ford Expedition)
in Middleburg, FL on August 31, 2010
r&r EGR valve, r&r EGR solenoid, blew out vacume tubes, have been told it could be catalytic converter becouse low exhaust pressure @ tail pipe? Teck said I have 4 cats and need to run diagnostic test. Service eng soon lite on and idels rough in gear, smooths out when up to speed.Egn has 166578 miles on it.
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on August 31, 2010
here is an article about Ford P0401 EGR code trouble shooting that I wrote to help people with this very thing. I seriously doubt it has anything to do with your CATs. It could be plugged up passages in your intake manifold, but do the tests as outlined in this article and you will find the problem. I used to be a Ford Dealership Journeyman Diagnostic Tech and have been Emissions Diagnosis in CA for over 25 years. I
deal with this stuff on a daily basis.
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on August 31, 2010
DPFE is a common failure. your tech is right. you need a diag to determine the issue

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on August 31, 2010
dandd is totally correct,clogged egr ports are very common as well as dpfe sensor.those are #1 and 2 most common failures.see it every day!
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