have egr tested to see if clogged up or egr bad. it may be cause of the knock but shold be looked at locally

sorry.the knocking sounds is on my left lower driver side.. i already test the egr valve and clean with carb cleaner including the throttle body all the way and clean the holes.,but still i have a check engine light and noise..i have a little knowledge in troubleshooting car but not like a pro.who knows a lot of car..i'm from philippines,all ford parts here are very much expensive.so i am asking online so that i can save a lot of money.thanks for the reply and i greatly appreciated who answer again my question..

try to isolate the sound if it's lower engine it may be a bearing kock or piston knock have it scanned to find the code and make sure your oil is full

i scanned it and the code is the same like my egr low flow P0401..i also check the oil as you said and it is find the dipstick is on full mark.i have a long issue about egr low flow but my expedition is rarely or seldom used.i jaz notice it when i drove the car for about a hundred kilometer then suddenly i hear the strange noise.i jaz hear that when i press the gas pedal or on cruising at higher speed like 40 or 60 mph.is that noise connected to my problem with the egr or i have a faulty DPFE sensor?thanks againt in advance and sorry for my bad english grammar.:-)

ok i went to thetips thing in our manual and 95%of the dpfe sensors are bad. But check to make sure then check the vacuum line leading to egr as it runs close to the manifold and may have a hole in it. I think these two things may straighten it out for you. sorry for not delving further into this the first time.

ok.i will provide some pics for reference.