cole w

i have a 97 f150 4.6l the nut on my egr tube rusted off the tube but was still on the manifold well me and my dad tryed to re thread the nut that was on the manifold still but couldnt so i put the nut or whatever back into the intake and had a guy at a repair shop weld over the hole that was on the manifold
well i regret doing that now because my check engine light it on i took it to auto zone and it said egr flow insuffient code p0401 i have way less hp and my throttle response is terrible before i welded over the hole this truck would get up and go on a dime but i cant do nothing about it now
so now im wondering what i could do to give it more flow and more hp
new exhaust maybe
new heads maybe
im new to all this stuff and only know what my dad has told me but im reading more and learning so hopefully some of you guys here could help me please
i want more flow and more hp
thanks
cole

Tim in Corpus

so the big " nut" that you screw down to hold the tube to the header is damaged? or on the intake side. you could cut the nut loose and should be able to pull it loose. take a picture? also it is a good idea to replace your dpfe with your egr valve. i always replace them both. your dpfe is usually bolted to the side of the intake and has 2 rubber hoses that connect to your exhaust manifold. holes in the hoses will cause problems as well. also make sure when you take the egr valve off the a bunch of carbon has not clogged up the holes underneath it. if you are talking about the threads of your intake manifold itself are damaged you should replace the intake which is a pretty easy job.

cole w

where the nut rusted off the tube on the manifold where i had it welded over

cole w

the two vacume hoses? im guessing that went into the egr tube they where just hanging there so dad told me to cut them short dont ask me why lol idk

cole w

the nut? that goes into the intake im guessing like i said im new to this stuff so i dont know what all the things are called

Tim in Corpus

looks like your going to need a new exhaust manifold. i dont know a whole lot about the aftermarket just stock stuff mostly. replacing the exhaust manifold is neccesary now. the 2 hoses are the dpfe hoses they see the pressure in your exhaust. the dpfe is what the hoses are attached to . i usually replace both the egr valve and dpfe together just to be sure the customers light wont turn back on with the same code. the egr valve is what you have pictured in that last post and there should be a vacuum line connected to the top of it. make sure the vacuum line is intact. that is how ford designed the system to work but i dont know about aftermarket stuff once again

scythefwd

JUST did this Tuesday and Wednesday. Dorman Parts off of amazon are inexpensive and fit well. The kit I got came with gaskets, the nub, and the flange studs. I also needed an egr tube and a set of studs. All in all, I think it ran me about 4 hours and 140 or so. Mine came off easier than most.. having just done the gasket a couple years ago.. about 10k miles.



EDIT:
Oh, and its entirely possible you wont have to replace the whole mani.

The tube that runs from the egr valve to the exhaust mani hooks up to a removable nub on the manifold. If you can get that removed, you just have to buy a new nub and egr pipe.