Question

2005 Ford F550 6.0L Diesel, what is the meaning of the engine code p0404?

Answer 1

HI there

This code is for a problem with the egr system. This could be the egr itself or the egr solenoid. Sometimes you will get this type of code if the egr port is plugged off. Here is some more info for you on this code.

P0404 FORD - Exhaust Gas Recirculation Circuit Range/Performance

Read more: https://www.autocodes.com/p0404_ford.html