2003 Mercury Mountaineer smog test failed

2003 MERCURY MOUNTAINEER
100,000 MILES • V8 • 2WD • AUTOMATIC
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326402
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I took my 2003 mercury mountaineer in for a smog check and all was good except my "service engine soon" light is on. The OBD code is po401 (EGR flow is insuficient). I don't know much about the EGR system but I did a visual inspection and did'nt see anything diconected ,etc. Can anyone tell me some likely causes or things to check?
Mar 31, 2009 at 6:26 PM
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JACOBANDNICKOLAS
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  • ASE Certified Mechanic
Remove the EGR. Chances are it has carbon build up and the valve is sticking.

Let me know what you find.
May 11, 2009 at 9:56 AM
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