Fuel System - 96 Caravan

My 96 caravan now runs out of gas when the tank is half full. I replaced
the fuel pump a few months ago (used unit), and has run fine for until now.
My theory is that the fuel pickup elbow (with fuel sock) has fallen off of
the pump. This would effectively causing the pump air once the fuel level
was about half way down the pump body. However, I thought there might be
another cause. Does anyone know if problems with venting/evap system could
create the same symptom?

 

Did you have the fuel filter replaced when you had the fuel pump replaced? A
clogged filter can lead to failure of the fuel pump because the of the extra
pressure it has to exert to get fuel past a clogged fuel filter. The full tank
keeps the fuel pump cooled. When the tank gets half full, then not enough of
the fuel pump is submerged to keep it cool and then it fails. Filling the tank
restores its function. At least that was my experience (my repair guy actually
suggested replacing the fuel filter first, to see if that would correct the
problem, but it didn't; however, it's believed to have caused the failure in
the first place).
Carl

 

Did you have the fuel tank replaced under warranty? The first round of
plastic tanks in the '96 vans were known to warp and were readily replaced
by dealers.

One of the signs of warpage, unfortunately, are running out of gas because
you think it's still got some in it. The other is only being able to put 14
gallons in a tank that has run dry.

My 2 cents.

Bob

 

Thanks for the comments. I replaced fuel filter the other day, and ran out
again today. I then filled to full, the tank taking 6 gallons to reach
full. The tank is the original warped tank, but the bottom is not warped
inward enough to cause a run out after 6 gallons.

Does anyone know if the evap/purge system can possibly cause a vacuum in the
tank strong enough to counter the pump pressure? That is the only
explanation I can think of, other than a cracked/broken/disconnected inlet
tube on the fuel pump.

I just hate to drain and drop the tank again, and find out the problem is
elsewhere.

Mike C