Help! Engine acting funny

[ESO6200]

Hello i am new to this forum so please excuse me if theres a thread for this topic .. But im having trouble with my truck . Its a 1984 gmc 5.0 305 .. So the truck starts up but it has a rough idle and dies after a few minutes .. I have changed the fuel filter , new spark plugs & wires ,new battery im stuck as of now as to what it can be .. I have a timing gun that ill use to check the timing . Please help with suggestions

 

[87scotty]

Fuel pump

 

[87scotty]

Carb? Clean?

 

[ESO6200]

How can i check if its the fuel pump? Iknoe that i have to get a pressure tester but where do i hook it up to? Also the truck stayed on when i took off the airfilter cover and had some hoses dosconencted


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[87scotty]

First thing can you hear the pump when you turn the key on take the gas cap off and have someone listen

 

[ESO6200]

Okay ill check that out thanks. Any idea on what it can if it werent the fuel pump?


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[Chevrolado]

How can i check if its the fuel pump? Iknoe that i have to get a pressure tester but where do i hook it up to? Also the truck stayed on when i took off the airfilter cover and had some hoses dosconencted


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Which hoses did you disconnect that then allowed it to stay running??

 

[ESO6200]

Which hoses did you disconnect that then allowed it to stay running??

Can you view pictures? Ican go ahead and show you


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[Chevrolado]

Can you view pictures? Ican go ahead and show you


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Post them in the thread.. I'm sure it'll help everyone with a little more pieces to the puzzle.

 

[ESO6200]

Will do im taking them right now


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[ESO6200]

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[ESO6200]

These are the ones ileft disconnected where it stayed on longer then having them connected . Im really stuck to as why it wont stay on. Maybe a dirty carb? Or ?


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[Chevrolado]

So by having those disconnected it will continue to run perfectly fine? Or you still get bad idle, it just doesn't actually die?

 

[ESO6200]

So by having those disconnected it will continue to run perfectly fine? Or you still get bad idle, it just doesn't actually die?

The idle would be rough still but istarted it this morning and it stayed on .ithen connected them and it turned on but the it like died out probally 10 secs later .


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[Chevrolado]

Alright.. Yeah I'm personally back to a fuel pump issue I think. The added air when disconnecting those might have prolonged the ability to run or something.. But still seems to me like a fuel delivery issue. I'd go back on the trail like the earlier posters were saying about validating your fuel pump is working properly and you have correct pressure coming out.