I have been troubleshooting a fuel problem for a few weeks now...

http://www.classiczcars.com/forums/showthread.php?t=38001

It's been an intermittent problem and I thought it was heat related but now I think it has to do with how much gas is in my tank.

The car has been running perfectly all week until I filled up on the way home from work today. At the first light after I filled up it died. The car started again quite easily and I was able to make it home by giving it some gas at the lights to keep the RPM's up. It now occurs to me that each time this has happened it has been right after a fill up and the problem goes away after a burn a couple of gallons.

I did a search and could find no reference to stalling or poor idle with a full tank. Anyone else ever experienced this?

Background:

1. Clean tank

2. New RX7 fuel electric fuel pump with mechanical pump still installed

3. New fuel filters.

4. New Ztherapy carbs

5. All new rubber fuel lines

6. Metal lines recently blown down with air

7. New fuel filler neck and cap

8. Fuel vapor tank bypassed as per the following post... http://www.classiczcars.com/forums/showthread.php?t=19034&highlight=fuel+vent

One more observation...the line going from the tank (formerly vapor tank) to the flow guide valve is full of fuel. I assume this is a problem but with the vapor tank bypassed I don't see how this would not happen with a full tank of fuel.:disappoin

Anyone done the bypass ever noticed fuel in the guide valve line?

This is my first post since I have always been able to find the answers to my questions with a search.

I am having this same problem and wonder if there was a solution?

The problem went away when I rerouted my vent line for the tank. I believe there was a low spot in the vent line that was filling with gas which made it harder for the tank to vent and thus stressed the pump (pumping against a partial vacuum and thus the carbs were starved. Just a theory but moving the vent line made the issue go away. Good luck!

Does it idle fine with the gas cap open?

It will not idle with the gas cap on or off.

Steve could you please explain what you did to rerouted your vent line.

Thanks

Bob