EGR

Just wondering. Was one of the parts replaced the DPFE sensor? Did you double check that the two vacuum lines to/from the DPFE sensor are connected and leak free?

IF replaced, did you use an aftermarket DPFE sensor? Ford has changed the calibration of the DPFE sensor. Either buy a Ford supplied unit or use one made by a well known maker.

Finally did you double check that the EGR passage ways inside the throttle body aren't clogged with carbon? Consider taking off the EGR valve and throttle body to clean/check the EGR passage ways.

If you delete the EGR hardware the PCM will still throw a DTC code.

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I'm going to assume that the P0401 DTC code is present even after all the above work was done.

Also wondering. Did you happen to notice that one of the "possible" causes is the reversal of the the DPFE hoses?

In general when working on my own cars I attempt to test first before replacing parts. If this were my car would start with some basic functional tests. For example using a vacuum hand pump to "activate" the EGR valve while the motor is idling. When vacuum is applied to the EGR valve the motor's idle should change. As the vacuum increases the motor should run worse and worse.

If so, this PROVES the basic EGR system can work when controlled.

If not, this PROVES that the EGR path is blocked or the EGR value itself isn't working. Obviously the next step is to figure out where's the blockage.

Once it is know that the EGR can work when controlled, then I would monitor the DPFE sensor to confirm that it responds to change in EGR flow. Here's where I think an advanced ODB2 scanner pays big dividends. Again using the vacuum hand pump on the EGR value while monitoring DPFE EGR flow, slowly increase the vacuum and note what the DPFE sensor reports to the PCM. Obviously the flow should increase as the vacuum is increased.

What to do next depends upon these test results.

Here's some information on a very affordable ($30) Windows based ODB2 scanner.

ForScan ODB2 scanner w ELM327 USB

Regarding the EVAP leak. Obviously all of the DTC codes will never go away until the gas tank is vapor tight.