Hey All, having some trouble with my 2002 F150, 5.4 XLT. A while ago I replaced the exhaust manifolds on both sides (they had been cracked for a long time). When replacing it, the EGR tube nut crumbled, and I hadn't gotten around to replacing it, but the truck ran fine (though it was pretty loud). Finally got to it today, pulled out the EGR tube, trimmed the end of the tube, and added a new flare nut.
As soon as I started the truck, I noticed a rough idle, and it threw the codes P0171, P0301, P0316. It also gets rougher under acceleration.
Is it possible that reconnecting the EGR tube caused problems with the EGR valve that hasn't been connected in so long? Or could not tightening the EGR tube enough cause the problem?

 

https://www.obd-codes.com/p0171
https://www.obd-codes.com/p0301
https://www.obd-codes.com/p0316

Read those and they may help you diagnose the problems. May not be related to the EGR.

 

Thanks for sending these over, I will take a look at them. I have been doing a lot of research on this issue before posting, but I haven't found anything for this specific issue. Just to be clear, the truck was running fine this morning (just idling in the driveway), then I worked on the EGR tube, now it's having trouble. That's what makes me think it's something that I did today.

 

Sorry for not following up. Turns out I disconnected one of the fuel injectors accidentally. Plugged it back in and the problems are gone!

 

congrats!