Check Engine Light

[dvozar]

:exp:2003 XLT 4.0 V6

This light just came on about 1 day after I replaced the air filter. Of course I through the old one out. Is it just a coincidence?

Code: P0401

Insufficient flow

Could this be from the new air filter I just replaced?

 

[J-RodG]

Code po401 has nothing to do with the air filter! It means something is wrong with the EGR system! First thing to check would be the DPFE also called EGR pressure sensor as fords are commonly know for these!