97 f150 P0401

I have a 97 f150 xlt 4.6, which keeps getting a code p0401
, I have changed the egr, plus the pdfe, plus all hoses, yet
it will run a while, and the po401 code will come back, I
re-pulled the egr back off, and tried to examine the port
to see if there are cloged, however i only have a open hole
which i can stick a screw drive all the way in, i saw a example of port close to the outer edge of where the egr
goes back on, but my do not look like this one"""""""
does anyone know what the problem can be.

Mac

you're in the wrong forum by the way! What happens if you use a vacuum pump to actuate the egr valve? does the truck stall out? if not then it normally means poor flow. If the valve is working then I'd suggest cleanning the throttle body and the ports all the way through and if recheck your dpfe. some jobber brands are of poor quality and or/not calibrated correctly

Split to new topic, and moved to correct forum.

1997 Ford Expedition
code 401
Removed throttle body from intake manifold found EGR exit port clogged with carbon and sludge.
Removed EGR valve and cleaned passage from EGR through intake manifold.
Used home made tool, bent 3/16 rod in large hook shape and small brass brush with lots of carb cleaner.
Cleared Code memory. Code has not come back!

10 times out of 10 thats what the problem is. Its also a good idea to replace the DPFE sensor also.