1989 K1500 was running fine and just quit. Not getting gas but I can hear the fuel pump start when I turn the key on. took fuel line off of TBI and seem to have plenty of gas flow but nothing comes out of tbi injectors. If i pour some gas directly into throttle body it runs. All fuses appear to be good including the fuel fuse. What could be the problem?

Kent, That sounds like normal operation.....see this link (https://www.justanswer.com/chevy/0z9bu-fuel-pump-relay-located-1987-chevy-silverado.html) The ECM shuts the pump down if the engine doesn't begin running in two seconds. I would bleed out the fuel line up to the TBI...crack the line at the TBI then cycle the key a couple of times until you see gas coming out of the line at the TBI. That will ensure you have fuel at the TBI, then try to start the engine. See the link for additional info.

Use a gage and check proper fuel pressure, with TBI, around 9--13 psi. There probably isn't a Schrader valve, to check fuel pressure tee into supply fuel line. Be aware of possible fuel pressure when taking fuel lines loose.

Check the coil, the control modual in the distributer, and the ecm. thats what controls the injectors.

The inline will not work,it can not get fuel threw the fuel pump in the tank,the fuel tank has to be removed,and the fuel pump changed out.

yes thats normal the prob is the fuel pressure regulator

it sounds like a fuel delivery problem. u may wanna check ur fuel regulater or anything that has to do with holding ur vaccum on ur fuel lines between starts. it seems like its priming itself to get it flowing then runs. lamost like the idea of a siphen

Idle control sensor.

I see you say that you have a new fuel filter but did you try replacing the fuel pump??? If not you can check the fuel pump simply by turning the key to the ACC position (thats as far as you can turn the key WITHOUT starting the truck) listen by where you pump the gas in and try to hear a low sounding whine if you cant hear it then it could be your fuel pump is dead and needs a new one....or it might be going dead.

when you crank the engine do you see fuel spraying from injectors .if you dont check for power at injector connectors one side should power and the other will be ground controlled from pcm.you can test with a 12 volt test for both. first test with test light grounded for power then test with test lead clip to battery to pos to the other wire from pcm while cranking engine light should flash.if it does turn key off again lean over tbi and have somone turn key on and listen for fuel circulating through tbi unit if you hear it without cranking engine replace fuel pressure regulator.

Not sure of your question, but it sounds like a bad fuel pump or clogged fuel filter. If it stops running after gas in tbi is consumed, it is likely the fuel pump.