Originally Posted by
driverman1
On my 2000 expy also with a 5.4 I had could for high DPFE Flow(I don't remember the number) it was one of the hoses going to the sensor it had hole burned in it both hoses were very brittle so I replaced both of them. if that is the problem need to get the hoses from ford dealer not they are not just vacuum hoses.
When I was doing an engine change in my Navigator I found that the OEM hoses were disintigrating from the outside as the rubber was flakeing off on my hands by just touching them. The hoses seemed to still be good and firm otherwise but, I replaced them with high pressure fuel hose and 3 years later they are still doing fine. I check them whenever I'm under the hood just to be sure. Better safe than sorry!