Hello everyone, I am having some difficulty with my pride and joy, my 85 iroc with a 5.0 HO L69 carbureted with a 5 speed. Only 14,000 original kms
She has been in my heated garage now since October resting thru winter. I start her every 3-4 weeks to run for 15 minutes. This time, upon startup it ran for about a minute perfectly, then as if I turned it off myself with the key, it died.
No struggle or slowdown of rpm, just BLAH!! died. I started it again right away and it fired, and died again right away. Now it will not start at all. It has a brand new camshaft operated fuel pump none of that in tank bullshit, and stinks of gasoline when I try to start and it. (Flooding)
I crossed out the alcl connector into diagnostic mode and I'm getting the normal code 12. Nothing is showing up. I am a diesel mechanic by trade so these old cars are French to me, I have no damned idea where to start.... It sounds like a ignition problem to me why would it up and die like that?
Any help is appreciated Its almost time to drive this sucker and its dead in my garage! O the humanity! Thank you!

 

Sounds pretty straightforward and ordinary:

Check for the presence of a 4-letter euphemism for "foreign matter" beginning with the letter S, in the needle & seat valve.

 

Ahh I figured it out... The carburetor fuel filter came with a stupid check valve that wouldn't open. I'm guessing the new pump dosent put out as much flow as the factory pump that was on it. Took the stupid spring and ball out and she runs perfectly. I hope this dosent add to the already excessive cranking time needed to start these damn engines but its better than having it die on me. Hah

 

ED..........GM had a specific reason for TWO fuel pumps in a HO.
Your finding out why.....................

 

If you're disabled the in-tank pump but are still pulling fuel through it, that's going to cause some restriction.

I have, however, experienced poor fuel flow that disappeared when the little check ball assembly was removed from the filter too. The carburetor shouldn't drain back normally, but if enough fuel evaporates over time to allow the needle to lift...