Question 2000 7.3 fuel system issue

[csarver]

I have a 2000 7.3 liter and it was not starting. I changed the fuel filter (of course I had to depressurize the fuel system when I did this) and the truck started right up.

I drove it, shut it off and it wouldnt start again. I popped the hood, depressurized the fuel system and it fired right up again.

question, do I have a fuel pump issue? If so, why does it only start when the fuel system is under no pressure???

Thanks guys
Chad

 

[iracemine]

wow! never heard of this. Anyone?

 

[JLDickmon]

wow! never heard of this. Anyone?

darn right wow.. that's contrary to theory...
something jacked up in the regulator be about my only guess

 

[Tail_Gunner]

The only thing I can think of is maybe somehow your getting air into the fuel system and relieving the pressure lets the air out?? I don't know, it's a stab in the dark.

on edit: I think I'd take the top off the fuel filter housing and look for anything that may be floating around in there.

 

[Dieselpwrdredneck]

i would check the regulator or see what kind of fuel pressure you are getting when it does start and when the no start problem occurs, that might help get ya pointed in the right direction

 

[csarver]

Thanks fellas.

This is definetly the issue. Ive taken the truck out a couple more times now and sure enough, it will not start until I depressurize the fuel system. Then it starts immediately.

If anyone has any info on how to check for air in the line and fix this issue if it is found that would be appreciated. I will also check on the regulator (currently not familar with this)

I will report back.

 

[WD40]

Have you taken the truck for a 50+ mile drive to see if this will clear up for you.
Doug

 

[csarver]

Yes sir. I drove it 60 miles and am still having the same issue.

 

[DaveBen]

You know, it sounds like you are sucking air into the fuel system from down stream (toward the fuel tank). There should be NO AIR in the fuel system. Have you gone over the entire fuel system looking for leaks/drips in all of the lines and hoses??

Dave

 

[JLDickmon]

you need to put a fuel pressure gauge on this to diagnose any further..