My suburban won't start.

[PlayingWithTBI]

also these truck are set up to run 9 to 12 psi fuel pressure.,,

No, GM says 9 - 13 PSI while the injectors are rated at 13PSI except ones from a 94-95 454 which are rated at 28-30 PSI.

At least one member here has run 28 psi on his TBI, and has posted the photos of his fuel pressure gauge as proof.

Guilty that was me on my 5.7L

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I put a 17 psi pump into my suburban, and it only reads 12 psi. is there any way the computer could be controlling the psi of the pump?

The ECM/PCM doesn't control pressure, the spring inside the throttle body does. 12 PSI is acceptable but I'd prefer closer to 14. With an AFPR (Adjustable Fuel Pressure Regulator) and various springs, you can dial it in to whatever pressure works best for you. I have an ACDECLO EP381 fuel pump from a 96 Vortec engine which is rated @155 L/Hr @60 PSI. Currently I'm running @ 20 PSI with an 18LB spring. YMMV

 

[Schurkey]

Ok. This is very uncomfortable. I put a 17 psi pump into my suburban, and it only reads 12 psi. is there any way the computer could be controlling the psi of the pump? I am at a loss for where to go from here. help!

1. Verify that your gauge is accurate.
2. Adjust the pressure at the pressure regulator in the throttle body. I have a 40+ psi pump in my '88; but since the regulator is set to about 14 psi, that's all the pressure the system develops.

 

[Teddygraham]

2 things here… if it’s getting fuel spray, it should try to run. I’d squirt an educated amount of starting fluid down its throat hole and see if it fires. Just to prove it a fuel problem.

Second, you may have installed plugs 3 months ago but that doesn’t mean they aren’t Fouled for various reasons. Just check and make sure they are clean still. If very wet, dry them out before putting back in.

Bonus, ignition control module could have left the chat. I really would like to think if any fuel from the injectors is present with a decent spray, realistically it should be getting enough fuel to run… even like crap