A few weeks ago I, my CEL lit up. Pulled the code and it was a P0401 "EGR Insufficient Flow". Read that it could be the DPFE sensor, so I just cleaned it. Shut the code off and it stayed off for a week. Now the CEL is back with a new code, P1406 "DPFE sensor downstream hose off or plugged. The EGR flow after the EGR valve is commanded closed."

The hoses are fine, should I just buy the DPFE sensor, since it's the second code relating to it now?

Truck is a '97 F150 5.4

 

Yes.