sigh a little pissed here please help po400 egr flow malfunction
 

i had a check engine light on in my car, i hooked my scanner up to it and it shows bank 1 sensor 1 heater circuit malfunction, so i go buy a new o2 sensor and have the dealer replace it, they couldnt replace it because the o2 sensor was stripping and was really on there(i tried it myself and couldnt get it out so thats why i brought it there) so they tell me i need a new cat, i get the new cat and bring the truck back in, they call me saying the 2nd o2 sensor is doing the same thing so i say go ahead and get another one

well AFTER spending about 1200 in a new cat and two new o2 sensors(bank 1 sensor 1, and bank 1 sensor 2) i was all fixed


driving home the damn check engine light came on, checked the codes now its giving me a p0400 which is egr flow, does this have anything to do with what they replaced? they replaced the pre cat and the two o2 sensors on bank 1, so i dont see why it would cause a egr code sigh need some help here what do you guys think.