Code P1406 is a code related to components of a Ford vehicle's exhaust gas recirculation system, or EGR. The code is signaled when an inexpensive sensor for the EGR valve known as the delta pressure feedback sensor, or DPFE, becomes outdated. When on-board diagnostics indicate code P1406, you should replace the DPFE sensor to prevent damage to the vehicle's engine.
Release the vehicle's hood latch by pulling on the release lever under the dashboard. Lift the hood and support it with the hood prop rod.
Look at the top of the engine and locate the EGR valve. It is on the intake manifold close to the firewall. Locate the DPFE sensor attached to the EGR valve.
Remove the two mounting bolts for the DPFE sensor with the socket and ratchet set. Pull the DPFE sensor away from the EGR valve and discard the sensor.
Inspect the mounting port of the DPFE sensor for any old gasket material and remove this material. Inspect the new DPFE sensor to make sure the new gasket or O-ring is present. Put the new DPFE into place on the EGR valve and secure it with the socket and ratchet set.
Lift the hood off the prop rod and lock the prop rod back into place on the core support of the vehicle. Close the hood.
