When shutting my fuel pump off to kill the car. The car continues to run until it drains the entire fuel bowl. I have an exrernal sight glass and I can watch it drain the bowl while it's idling with all the power shut down.

It's a 51mm IDA Weber with a Mallory 140 pump. Mallory 4309 return regulator. Reads 4psi while fuel pump is on with car off and 3.5psi with car idling. -6 fuel feed and return.

 

What do you expect? Unless your pump being off also cuts the ignition.

 

I've never had a set of Webers do this before. I thought it may be something wrong.

I have a battery kill switch which kills all power. It still idles with everything killed.

No big deal really, I'll just pretend it's a built-in mechanical turbo timer.

 

alternator diode

Oh, and your ignition switch is supposed to go to ground when off. Something tells me yours is not doing this. You modded your ignition, didn't you?

 

The car has a push button start. Not a single wire in the car originally from Mazda.

I will be removing all wires and building a better, safer harness real soon. I'm drawing out the stock schematic for it currently. I'll try and set it up to kill power to ignition when the fuel pump power is shut down.

 

Sounds like a plan.