I think I've finally found the cause of my recently-atrocious gas mileage. When the truck is running and for a short time after I shut it off, I can see fuel dripping about twice per second off of what appears to be the fuel pressure regulator. I haven't taken things off to see if that is indeed what's leaking, but if it is the FPR, how hard is it to replace? Or is it just an O-ring seal inside that might be leaking?

Knew there had to be a reason why my truck smells of gasoline after it sits for a few minutes.

 

Disconnect the return hose, vacuum line and unscrew it. I might have undone the EGR tube for access.

 

Is it the pressure regulator or the pulsation damper? Fuel pressure regulator is near the firewall, pulsation damper is near the front, under the intake manifold. Both are known to leak with age.

 

I was wondering if this truck had a fuel pulse dampener, as my Mustang does. It is indeed the one in front, so I guess that's it. Is it the actual dampener that goes bad or just the O-ring or seal that seals it?

I think I'm getting about 8 mpg lately with this fuel drip.

 

I know that the screw in the middle sometimes backs out to the point where it falls out and begins dripping fuel through the hole.

They're not repairable so you'll need to get a new one. I believe they're a dealer item only.

 

There is an o-ring.