Gasoline Leak

[MikeP]

When my 91 Explorer 4x4 XLT is cold (overnight temp below about 55F), when I start the engine in the morning there is a gasoline leak which pours (dribbles) liquid gasoline onto the ground under the center rear of the engine. After the engine heats up (maybe 3-8 minutes) the leaks stops. This has been happening periodically for maybe 5 years but Ford techs have not been able to find the leak (they have kept my vehicle overnight, run it for hours, etc.). I suspect some fuel connection (fuel pressure regulator ?) is heating up and expanding sufficiently to stop the fuel leak. Any suggestions as to what is going on? I have about 270,000 miles on this Ford (got it new in July 1990).

 

[fixxxer]

That does sound like the FPR, either the O-ring seal or the FPR diaphragm. If it was the FPR diaphragm, you would be running way rich though.