Trouble Code PO401 EGR Flow Insufficient Detected
 

My daughter in law brought her car to me about the check engine light being on the other day so I hooked up the code reader and got PO401 EGR Insufficient Flow Detected. I took the EGR valve off and cleaned it and the EGR port on the intake manifold and put it back together and it solved the problem. I just wanted to post this in case anyone else ever gets this code, but be sure to clean the port in the intake. Her car has a port about the size of the end of my smallest finger and was nearly completely stopped up. The auto parts store had told her she needed a new EGR valve. WRONG!!!

That is why I use Seafoam regularly. Carbon deposits are bad.

I don't think SeaFoam will help these Johnny,
The port goes through the intake for about 7 inches and is quite small as he stated.
It gets plugged with carbon from the cooling exhaust gas passing through it.
in earlier models ford ran coolant passages beside it to keep it hot so the gasses wouldn't coke up, in later models they widened the passage. And all Fords have this problem. I've cleaned hundreds. From Crown Vics and Lincolns to Escorts to F series trucks.

I was a Ford tech for a few years. The police Crown Vics (CVPI) got regular water or seafoam treatments.

thanks for your info almost spent to much money!
 

:)