Almond81Vette Any help will be great for I am at wits end now on this fuel or lack of fuel problem. Sorry for long post but want to give as much info as can.
1981 Corvette – stock 350 engine, auto trans, Q-jet carb, ECM and all parts in place and working
Problem: Sunday drove home 15 miles in about 90 degree temps, got to garage, stopped engine while got out to open garage, cranked engine drove in and stopped engine again. Open hood and waited a few minutes and then proceeded to crank engine again and made a slight idle adjustment, to increase
With assistance from the wife I unconnected the fuel line to the carb and had her spin the engine, no fuel came out (but as later discovered may not have spun the engine long enough).
With no fuel from line I jacked up the vette and went underneath. I first unplugged line from fuel tank to fuel pump and had fuel. I then disconnected the outlet fuel line from the fuel pump and she spun the engine and I had fuel there. I then blew out the fuel line from the pump to the carb, good air flow, no restrictions.
I connected everything back underneath and went back engine side. Before reconnecting line to carb I had her to spin the engine again. Still no fuel but then I told her to spin engine until I told her to stop, she was only doing it maybe 2 seconds at a time and even this short of time initially.
The last time I had her spin the engine I got fuel out in about 3 to 4 seconds so I had fuel to carb now. One of my thoughts is now I may have had fuel initially just didn’t spin it long enough, don’t know for sure.
Reconnected line to carb, spun engine, checked fuel thru jets, no fuel. Re-spun engine and pump gas pedal a few times and re-checked the gas thru jets, had fuel now. Started engine up, she ran fine.
Past work that has been done:
New rebuilt Q-jet carb from Ecklers; new manual fuel pump; gas tank cleaned out and new sock on fuel pick up line; lines from tank to fuel pump blown out; fuel line from fuel pump to carb replaced with new line and line wrapped with 500 degree heat cover. New ECM box installed, new power chip prom in ECM. New ERG valve installed; New fuel filter (goes inside carb, replaced 1 month ago).
Again I wanted to give as much info as possible to seek the best advice on where to go next.
LouiecrAlmond81Vette 
danascar
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DanT
Almond81VetteI have run the vette when hotter, even with AC on and not have it to lose fuel to carb. This really is getting me since it does not seem to be a definite cycle, timing or use that will create the problem. When we did the other work to address possible vapor lock on the fuel line from pump to carb we installed the 500 degree heat sleeve over it since before just a naked steel line running up the front of the block.
What else do you propose could be vapor locking? The fuel pump? I had fuel from the outlet of the pump when I tested it about 10 minutes after loss fuel to carb's throat.
yostusota
danascar DanT
Almond81Vette 
dskopp
Adams' Apple
made a slight idle adjustment, to increase
If you're moving the throttle by hand, a Quadrajet requires a pretty quick movement to actually push much fuel thru the squirters. If you were just slowly working the throttle, it may not have pumped any fuel like that.
"The engine just stopped"....as in just shut off like you turned the key off? If it just shut down like that, then chances are the ignition module in the distributor is about to take a doo-doo. That is one of the most common failure modes for them....they'll just shut off. It may start right back up after a few minutes of cooling off, or it may take an hour or so to cool enough to start back up. You've done a ton of work on the fuel system....I kinda think the problem is somewhere else. The fuels today will RARELY create a vapor lock....the stuff is just not volatile enough. Of course, if you get any metal carb or fuel line hot enough, it will certainly boil the fuel, which is what a vapor lock is. You'd prolly have other problems too if it was running that hot, imho.
I'd be checking the ignition system.
The electronics on your car(ECM) really only controls the idle fuel mixture, and the timing. 
hth
Joel Adams
C3VR Lifetime Member #56 
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"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"
Almond81Vette ranger3I agree that it sounds like the module. That's exactly what mine did and a new module cleared the problem. It would just shutoff and would not restart until it cooled down.
Adams' AppleJoel Adams
C3VR Lifetime Member #56
My Link
(click for Texas-sized view!) NCRS
"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"
yostusota Almond81Vette Almond81Vette Adams' AppleJoel Adams
C3VR Lifetime Member #56
My Link
(click for Texas-sized view!) NCRS
"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"
yostusota Almond81Vette Adams' Apple
Joel Adams
C3VR Lifetime Member #56
My Link
(click for Texas-sized view!) NCRS
"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"
dskopp
ejwbhowellyostusota Almond81Vette manchestersharkAlmond81VetteJust to update all on this issue, the vette has been at Corvette Etc in Charlotte for the last week and they have been going over the entire system and most main parts such as fuel pump checked out, the TPS and choke had to be adjusted but the mechanic feels the main reason for my problem of fuel stoppage was the "S" hose from the steel fuel line running the frame from the tank that connects to the fuel pump. This hose was soft, not hard as an original hose should be. Since engine was cranking and we could not make it loss fuel again this was what was changed out and now testing the vette on the road. So far all working as should.
I was not aware of this hose being so special and that a standard rubber hose was not proper for this operaton so hope this is the fix and if any of you have similar problems may want to check your "S" hose as well.
