Oldsmobile/Buick Repair: 1999 Olds Aurora will not start, oil pressure switch, fuel pump relay

Question
-------------------------As said earlier, the fuel pump will run for a few seconds and then quit (have fuel oultlet line hooked to tygon tubing and run to jug)
If my fuel pump is good, why do I not have any fuel at the schrader valve on the fuel line to the injectors?
Followup To
Question -
Changed the front 4 plug wires on my 1999 Olds. Aurora, 4.0. Engine would turn over but would not start.  Found wires 6 and 8 reversed, changed, still does not start.  Was told to check fuel pressure/flow at schrader valve on fuel line.  Only a small spurt of fuel and then nothing while trying to start. Found pump, disconnected outlet hose and ran tubing to a jar.  Pump starts then stops after pumping a few ounces of fuel.  Did the fuel pump randomly fail?
Answer -
Fuel pump test:

1. Get yourself a helper.

2. remove the gas cap.

3. have one person listen in the gas tank at the gas cap opening.

4. have the other person turn the ignition switch to the ON position ONLY so as the dash lights come on. Do NOT attempt to start the engine.

5. As soon as the ignition key is turned to the ON position, The person at the gas tank should hear the fuel pump run for TWO SECONDS and then it should STOP.

6. Does it ?.


If you do NOT hear it run, in most cases the fault is the fuel pump.



let me know.

QUESTION: will the vehicle attempt to run if you spray a little starting fluid into the intake manifold ?. If it will, The fuel pump would be suspect as being faulty.


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Answer
OK, Here is how the fuel pump circuit works.

1. When you first turn ON the ignition to start the vehicle the computer sends a 2 second signal to the fuel pump relay of which enables the fuel pump to run for ONLY 2 seconds and then STOP. This primes the fuel system with fuel pressure and volume.

2. Once the engine starts, the computer BY-PASSES the FUEL PUMP RELAY and sends a constant continous battery voltage signal to the oil pressure switch which CLOSES due to oil pressure and sends battery voltage back to the fuel pump in the fuel tank to make it run constantly until you shut OFF the engine.



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