1989 Chevy Dully 5.7 V8 Engine Fuel Problem


Asked by Sep 10, 2015 at 03:00 AM

Question type: Maintenance & Repair

Hey my truck had a bad fuel injector, i replaced it, got new fuel
filter, it was clogged, truck runs but dies like its not getting fuel
when i give it gas. does any one know what psi my fuel pump
should release? also what else it could be and how to check the
regulator and if my fuel pump in working properly? Please help, i
have the pressure tester. where do i begin?

6 Answers


here is what you can do I believe but please dont hold me to it that year truck should be running about 56 LBS of pressure. you can call any parts house tell them what you have and they can tell you what the pressure should be. when you turn on the key the pump should pulse on for a cupple sec to build pressure and then shut off when pressure is astablished. if you have a gauge hooked to it you will see this. when you go to start it you will see the drop in pressure but the fuel pump should compinsate for the drop. please forgive my spelling its late and I had a busy day. so let me get this straight when you give it gas it dies? how about if you start it and it idles does it die or slowly die or does it run at a idle till you give it gas then it dies. this will help us know when it is dieing and what the problem might be.

1 people found this helpful.

cold will not idle, once warm will idle, take off tries to go but falls on face. no power, sputters. when i turn key and check fuel pressure past the in line filter shows 10psi


i have the 350 small block TBI fuel system

1 people found this helpful.

i think on a gm TBI 56lbs is wrong your 10 would be ok. 56 for port injection i think. but you might have a fuel regulator problem or a failing pump. try blocking the return line back to tank. if the truck runs ok it is your regulator spring is bad


oh i found this might help http://www.howstuffinmycarworks.com/GM_TBI_fuel_pressure.html


TBI 10 to 12 lbs. (12 most desirable) 10 lbs. is getting weak. Vortec motors, 56 lbs. min.to 62 lbs.

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