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'93 Lumina won't start

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.

Reply to
kj_link
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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.

Reply to
=?x-user-defined?Q?=AB?= Paul

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.

Reply to
William Dryden

That engine is MPFI.

Reply to
=?x-user-defined?Q?=AB?= Paul

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.

Reply to
William Dryden

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.

Reply to
=?x-user-defined?Q?=AB?= Paul

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.

Reply to
kj_link

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

-- William

No trees were destroyed transmitting this communiqué, however several million electrons were severely inconvenienced.

Reply to
William Dryden

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