I had been experiencing some oil consumption and a cold start rev-up(strange), that would rev the engine up to ~1800rpm on fire up then it would correct back to idle immediately.
No CEL's, and I was doing alot of boat towing so considered the consumption as normal although not too big of boat or hilly terrain.....6500#'s on mostly flat roads.
When on a camping/boating/fishing trip this fall, I got ~5mpg on the way to the campsite, then the idle started to surge really bad and threw a CEL.
I could hear some noise like a vacuum leak that was inconsistent, so I removed the cover on the throttle body and found that the EGR hose had collapsed at the sharp bend going into the TB, and cracked/rotted causing the leak.
It was also very oily inside and had obviously been feeding the engine some motor oil. The collapsed hose was allowing the engine to pull alot of vacuum on the EGR valve is my reasoning. The surging was making the truck nearly undrivable so I ended up zip tying a foil hamburger wrapper around the hose to seal the leak and drove to the nearest Napa. The whole hose/EGR valve thing is a ford only part, so I ended up using a little J-bend rad hose to perform the fix in the Napa parking lot and it took about 20 minutes.
Appproaching the next oil change and I am still right at the "full" on the dipstick so it appears that my oil consumption is gone as well

 

yes i had the same problem with the idle.. and same fix. autozone has the correct hose but its about $28.. i just found another curved hose and cut it down. dont care for autozone much but the guy was cool enough to let me look through the hoses and find one.. ended up costing $4

 

Ford eventually figured out the issues and changed the hose for the 2004 models. The little elbow was usually the culprit.

 

ya if it happens again im just going to run a longer hose out the front of the throttle body , around the front side of the throttle linkage and then down to the pvc.. alot less of a curve

 

The rad hose I used was thicker than the oem one, hopefully it will hold up much better. It was kind of a hook shaped hose used from the water pump to intake on a dodge that fit the bill IIRC.