My 03 f150 has the 4.6. Engine light has been on for some time now. Finally truck died. Code was for faulty EGR valve. I replaced it reset the codes as well as the computer and it’s still stalling!? No performance mods or anything to list. Please help!

 

What was the exact numeric code?

 

p0401

 

The 4.6 is notorious for plugging up the egr passages from what I understand. Read this:

https://www.obd-codes.com/p0401

 

If a new EGR valve didn't fix it, either the passages in the throttle body elbow are plugged or the DPFE is bad.

 

This may of been it putting back together now

 

Same issues truck will idle at 500 rpms if I feather the gas at starting and slowly let it idle down if I give it gas and let off she stalls

 

Now you probably have a bad IAC.

 

Cleaned the IAC with brake clean and she works now will be replacing soon to avoid future issues