i believe that the valve you have pictured is a shut off valve designed to prevent dieselling when the car is shut off.the wire going to it is power all the time when key turned on.now,this carb is junk.it is made of aluminum and as such IT WILL WARP causing you to believe that the gaskets have failed.it's best use is as fishing weight.company called J.A.M. engineering in california came up with direct replacement of modified holley[100 times better]easy fit even for novice.david poole european performance dallas tx 2149567007.