This summer my '89 vert had an intermittent fuel leak that only happens after the car has been sitting for over a week (but not always) where after start -up, fuel drips on the ground , just under the firewall, center of car. No obvious fuel leak looking at engine from top. Have driven away and drip stops after about a block and will not leak again if driven regularly . Could not duplicate problem for mechanic . Anyone had this problem ? wondering if maybe an issue with the return line from the secondary fuel rail

 

i think for that you'd want to wait until you think the car is going to do it, and then jump the fuel pump test connector and run the pump and see what happens. you might have to just let the pump run, or try it a few times.