Will not start, injectors not getting fuel

JEFFMARTINHYKO

MEMBER
1990 BUICK REGAL
166,000 MILES

3.1 MFI Will not fire up. I shot fuel into the throttle body and it fired right up, seems that the injectors are not all working, tries to start but barely. Check the wiring to injectors found some smashed, corrected that issue, still same problem. Does anyone have a wire diagram and/or what I should be getting at injectors. Should they have constant power which is what I seem to be getting. Replaced crank sensor, coil packs, plugs, wires, fuel pump, and filter. Does not throw any codes. I did check all wires from computer to injectors for continuity all have it.
Have power to injectors, should they pulse? They only show power constantly.

10 Replies

RASMATAZ

MECHANIC
75,992 POSTS

Sounds like the fuel injectors ground circuit is out-Have the computer tested-

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Sunday, November 3rd, 2013 AT 1:01 PM

JEFFMARTINHYKO

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6 POSTS

How do I test it myself

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Sunday, November 3rd, 2013 AT 1:33 PM

JEFFMARTINHYKO

MEMBER
6 POSTS

Does anyone know what voltage I should be getting at the injectors and which wires and colors to test. A diagram would be great

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Sunday, November 3rd, 2013 AT 1:33 PM

JEFFMARTINHYKO

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6 POSTS

So what you are saying is that the fuel pressure should stay and hold pressure even with key turned back off? The fuel pressure regulator was replaced also. I was thinking the pressure was low. And that it should hold even after key was turned off. What would cause the fuel pressure to go imeadiately back to zero when I turn the key off.

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Sunday, November 3rd, 2013 AT 1:36 PM

HMAC300

MECHANIC
48,601 POSTS

Look you have low fuel pressure you have to fix that first. A faulty fuelpump check valve will cause what you are experiencing.
A faulty in-tank fuel pump check valve will allow fuel in lines to drain back to tank after engine is stopped. To check this condition, turn ignition off, disconnect fuel pressure line at fuel rail, remove filler cap, and connect a radiator test pump and apply 15 psi (1.0 kg/cm2 ) pressure. If pressure will hold for 60 seconds, check valve is okay injectors have 12.2ohms resistance. Besides you need wha tis called a noid light to test injectors not a probe. Here is injector wiring colors

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Sunday, November 3rd, 2013 AT 1:46 PM

JEFFMARTINHYKO

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6 POSTS

Thank you very much I will check all of what you said and get back to you. Again thank you so very much.

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Sunday, November 3rd, 2013 AT 1:55 PM

AIYELAGBE

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4 POSTS

On how to check the injector wires, one is ignition current while the other one will be the ground wire, if it correct then your injectors are bad if not check the whole fuse in the car.

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Tuesday, November 5th, 2013 AT 2:49 AM