'93 Lumina won't start

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Any help would be greatly appreciated.  Here is the situation:

Car won't start but cranks good.  When ignition is turned on, I can
hear the fuel pump cut on for a couple of seconds.  When this happens,
fuel leaks out of the throttle body.  If I manually open the throttle
valve a good amount pours out (about 1/4 cup).   If I crank it for a
while, it just pours out of the throttle body.  If I depress the
pressure check valve on the rail I get very little if any pressure, the
gas just barely bubbles out.  If I pull the fuel pump fuse, I can get
it to turn over and run until the fuel in the lines runs out.  I tried
pulling the fuse, starting it and putting the fuse back in, but it just
dies.  I have run out of ideas.  Could it be a bad fuel pump?  I'd hate
to drop the tank and replace it, only to find it was somthing else.

Thanks in advance for any replies.


Re: '93 Lumina won't start


kj_link@yahoo.com wrote:
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Assuming a 3.1, for fuel to come out the throttle body the entire intake manifold
would have to be full.  It will not crank in that situation.

Re: '93 Lumina won't start



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If the fuel pours out of the throttle body, it is not the fuel pump.  There
has to be something wrong with the fuel seals on or in the trhottle body  It
soulnds to me like the engine is flooded and that is why it will not run
with the fuse in.  When you first start it up with the fuse removed, there
was probably a very thick cloud of black smoke out the tailpipe.  If that is
correct, that confirms a flooded engine.



Re: '93 Lumina won't start


William Dryden wrote:
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That engine is MPFI.

Re: '93 Lumina won't start



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the
just
hate
There
It
there
that is

That does not mean it can't be getting into the manifold and going into the
cylinder with the air as well.

BTW,  Do not run the engine with raw gas on the intake.  It will get hot
enough to ignite.



Re: '93 Lumina won't start


William Dryden wrote:
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That is true.  I am curious though as to how you would explain gas pourin=
g out the
throttle body on a mpfi?
The autoignition temp of gasoline is 495F.  Hopefully his engine won't ge=
t that
hot.

Re: '93 Lumina won't start


Thanks for all the replies.  It ended up being the pressure regulator.
It was allowing gas to backup in the vacuum line directly into the
throttle body.  It was a personal nightmare replacing it too.  I am by
no means an automobile repair expert, so when I finally got the bad one
pulled and replaced it, and got everything back together, I was high
fiving myself.  Well, I started it up and no more gas leaking out and
it seemed to run ok.  Then I noticed a large gas leak from one of the
injectors where the fuel junction.  Here is the stupid part.  I could
not tell where the gas was coming from, so I took off the plenum and
started it up.  The large collection of gas ignited and there was a
small bonfire right on top of the manifold.  I got it put out, but
melted the vaccum lines and had to get those replaced, as well as
getting the leak taken care of.  After all that, it is running good so
far, the gas smell is finally gone, and no leaks noticed yet,knock on
wood.  Live and learn, and lucky not to get burned.

Again, thanks for all the responses.


Re: '93 Lumina won't start



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I'm glad you got it fixed without getting hurt.  I did warn you about the
fire.


--
William

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