1991 Mazda 626 1991 626 Fuel problem

1991 MAZDA 626
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NICKNOBODY
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1991 Mazda 626 4 cyl Front Wheel Drive Manual

After doing a long block swap I am not getting any fuel to the cylinders. The fuel pump is working and the fuel pressure after the fuel filter is good. The injectors are clicking so they seem to be working. When I tried to pump fuel into the fuel rail it seems to be blocked, also now there seems to be a buzzing/humming coming from the BAC(I believe), the sensor/valve with two wires, on the the throttle body. Any insight or advice would be greatly appreciated. Thanks
Feb 28, 2009 at 1:04 AM
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RASMATAZ
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You said the fuel pressure is good-my question what is it-this is where we start Ill be waiting
Feb 28, 2009 at 1:12 AM
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NICKNOBODY
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38 psi. I have also tried pumping fuel into the fuel rail with my hand pump.
Feb 28, 2009 at 1:24 AM
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RASMATAZ
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This 38psi is it with vacuum on the regulator or without

With vacuum should be 27-33psi and without vacuum 34-40psi
Feb 28, 2009 at 3:21 AM
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NICKNOBODY
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no vacuum.
Feb 28, 2009 at 3:40 AM
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NICKNOBODY
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Like i stated before i am unable to pump fuel into the fuel rail. Can the pulsation damper cause this?
Feb 28, 2009 at 3:43 AM
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RASMATAZ
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I'm lil bit confused here-you checked the fuel pressure and it gave 38psi is this while the engine is running and the vac hose is disconnected from the fuel pressure regulator.

Double check the injectors if its spraying fuel
Feb 28, 2009 at 4:05 AM
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NICKNOBODY
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the fuel pump turns on and consistently runs with key in the on position. no vacuum because I am unable to get the motor running.
Feb 28, 2009 at 4:11 AM
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RASMATAZ
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Use a starting fluid and spray into the throttle body-Did it fire up and dies out
Feb 28, 2009 at 4:17 AM
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NICKNOBODY
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yeah, I can start it with starter fluid.
Feb 28, 2009 at 4:18 AM
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RASMATAZ
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I don't think your injectors are pulsing meaning opening and closing-test the injector's resistances if okay -The computer fuel injector ground drivers defective
Feb 28, 2009 at 4:26 AM
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NICKNOBODY
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Ok, I think I found out what the problem is but I am unsure what I need to do to fix the problem. When I turn the IGN to ON fuel pressure is 38-40psi but when I crank the engine the fuel pressure starts to drop, if I continue to crank the engine the fuel pressure will drop to almost nil but as soon as I stop cranking the engine the fuel pressure jumps back to 38-40psi.
Mar 6, 2009 at 9:44 PM
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RASMATAZ
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Check the fuel pressure regulator
Mar 6, 2009 at 10:21 PM
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NICKNOBODY
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I replaced the fuel pressure regulator to no avail.
Mar 6, 2009 at 11:26 PM