Insufficient EGR flow

2000 Mercury Sable GS Wagon. 3.0L V6 OHV engine, 105000 miles, automatic. My check engine light came on. The OBD-II code is P0401, EGR insufficient flow detected. Would this be a problem with the EGR valve, the back pressure sensor, or the solenoid?

You can check this out for some quick info:

The best case is to have a repair manual to do the right tests on all of the system components to verify where the problem is. The EGR system parts aren’t cheap so it might even be worth buying the manual just to sort this out.

You might be able to get the right procedures & specs from Autozone’s website. Quick & free registration, plug in your car’s specs & find the online Repait Guides.

FYI: ford’s problems with the DPFE sensor are legendary. I’d place a small early bet there - but test first.