My car is on 45K, and I suspect the previous owner (to 34.6K) didn't really do many long trips to keep the system clean. I however tend to do a mix of 200>500 mile round trips in a day and commutes,so today, I stripped the throttle body and egr off and was stunned at how clean the egr was!
it had about a 1mm thick coating of hard compacted soot, very little loose flaky debris, the solenoid moves very freely and the entire unit was in good shape.
The throttle body had some thick sludgy paste type oil on the butterfly and around the hinge points.
The inlet manifold had similarly very little crud around the air flutes from the egr to the throttle within the manifold itself so I scooped what was there out wiped it all over and rebuilt it.
there was nothing to see in the pics as the post on how to remove is as detailed and shows far more than anything I observed.
OK I rebuilt everything, and the idle seems a bit smoother and the throttle a bit sharper but this is probably all in my imagination if you get my drift?