P0404 code, wouldn't crank, then it started and ran rough

Code d'erreur P0404 : gravité, causes et coût de réparation code p0404 The code may be thrown due to a clogged cat with too much back pressure anyone here ever encounter that or have any other thoughts? code p0404 Monte Carlo Repair Help - P0404 engine code

code p404 P0404 = Exhaust Gas Recirculation Open Position Performance Sets when the difference between the desired EGR position and the actual EGR position is more than