engine light nuisance

I have a 1997 F150 4..6L, I replaced the EGR valve, sensor and regulator in efforts to stop the engine light from comming on with and EGR low flow error. To no avail the engine light still comes on. The idle is a little slow but engine does not die, on a stop the rpm's will slow to 3-4K and then jump back up to normal range 6-8k.
I have traced the wiring and have not found any shorts and have tested for voltage flow to the sensor and all appears well.
Any suggestions? Anyone

A friends 97 f 150 EGR port was so plugged he had to drill it out. If you didn't clean it good and blow out the port this is probably your problem. Also check the DPFE sensor. This was the problem on my 97 5.4L.

THANKS FOR THE SUGGESTION, The port barely had any residue on it it was fully open but I cleaned it anyway.
I replaced the PTFE sensor, the only other thing I can think of is there are two hoses one HI and one REF. The REF hose showes some signs of internal wear and clogged the REF port on the PTFE.
Im stuck on this one.

Is this a hose or steel tubing anyhow go to a junk yard or dealer and get another hose. If you can't clean the sensor get a new one they are a problem area on this car.
At least inspect and clean the hoses.

make sure the ref and hi hoses are on in the right spot on the presser sensor

There are 2 ports that get clogged with carbon. The upper part of the intake must be taken off.(The part of the intake where the throttle body bolts to)4 bolts hold it down. Take the EGR valve off and then clean the 2 ports that go into the EGR port. Most times I find the ports plugged and thats why you always get a low EGR flow code.