2003 Hyundai Sonata PO401 check engine code

toodog733 · Posted at Mon Sep 15, 2008 11:41 am

Engine Performance problem
2003 Hyundai Sonata 4 cyl Two Wheel Drive Automatic 101000 miles
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After researching many articals on this trouble code (PO401) EGR insuffient flow I was first lead to believe a bad EGR valve or actuator solenoid was at fault. Then I came accross some information on the differential pressure sensor EGR (DPFE) a thought it may be to blame. All the articals I could find were on Fords and I have a Hyundai. My question is, do all cars use a DPFE sensor, specificly does my 03 Hyundai Sonata have on and where is it located, and what do you think I should do first.

rasmataz · Posted at Mon Sep 15, 2008 11:51 am

Clean out the EGR valve/passages and make sure its getting vacuum thru the vacuum solenoid