Yeah that happened to mine too but i just bridged the wire at the 3 pin connect so it continually pumped.....
The problem I think is that while the engine is cranking power is taken away from the coil and dizzy......
I think what I'll have to do is find which connection on the ignition switch is for the coil and run a wire direct to the coil.....
bypassing all the sender units and the such....
This problem seems to be common when they are gettin on in age like me. All SPARK NO Fire
John