07 major loss of power

[Sholmes1990]

Hi guys

Just a couple weeks ago I had an issue with my truck gettin up to 55 an lossing power and shaking real bad. I changed the fuel filter and cleaned the egr valve which was pretty bad. Now today I ran Into the same issue except now I have a po405 circut low egr which idk what that means. Should I just replace the egr valve? I don't know why that would make me lose so much power tho. Thanks guys any help would be great

07 powestroke 6.0 86k miles

[Sholmes1990]

Btw stuck on roadside in fear of doin any damage can't get her above 50 without dropping back to 35 and shaking