Re: [DML] what would a bad fuel accumulator do?

["Walter" <Whalt@xxxx>]

Andy,

It's definitely not the accumulator. When the accumulator goes bad, you
have problems starting the engine only when it is hot. Your symptoms are
the opposite of this condition.

Your fuel pressures should not be anywhere near 100psi ever. There is a
chance, however slight, that your fuel leak was related to this high
pressure. Maybe you have a clog in the system, but not likely. I think the
problem is that you have a bad control pressure regulator.

I suggest first checking to see if a clog might be your problem; although, a
more experienced mechanic might suggest a better approach. To do this,
disconnect the fuel return line from the control pressure regulator. Blow
some compressed air into this line and listen for bubbles in your fuel tank.
It should sound like blowing air into a straw in a glass of water. But
first remove the fuel tank cap to stop pressure from building up in the
tank. Air should move easily through this line. I suggest using clean dry
compressed air from a shop air supply. Use an air nozzle that has a rubber
tip to help seal around the hose opening to force air into it. Adjust the
shop air regulator to a low psi setting so you don't go blowing megga gas
bubbles. 10 to 20 psi should be plenty. If this line isn't clogged and you
are measuring over 3.8 Bar fuel pressure between the fuel distributor and
control pressure regulator, then I am quite sure that you have a bad control
pressure regulator.

Some caveats:

Make sure your fuel pressure gauge is accurate. Hook it to a shop air
compressor and compare it with a gauge that is known to be accurate. A tire
pressure gauge will let you know that you are at least in the ball park.

Do not re-use the copper seal rings. Those are not meant to be re-used.
They are cheap, and the DeLorean vendors sell them. Buy extras to keep on
hand. Once you master this, you may be testing pressures on other people's
DeLoreans.

Tighten the fuel lines back with a torque wrench according to the specs in
the service manual.

Keep a fire extinguisher (or two) handy, and ALWAYS keep a big one in the
car at all times. When I say big, I mean at least 3kg of white stuff.

Wear safety goggles.

On a side note, be sure that the shop that fixed your fuel leak did it
properly. If they replaced a hose, then chances are they replaced it with
the wrong kind of hose. Typical fuel line is not made to run at these high
pressures. If a line breaks and catches fire, then it works like a blow
torch.

Let us know how it turns out.

Walt Tampa, FL