I would love to know how that would happen? I unhook the fuel pump relay on all my cars when I have to get into the fuel rail. I dont see how this could possibly happen. if its not on or receiving power there's no way it could fail. the car will simply stop running as soon as the in-line pressure is bled off and no gas can be pushed through the injectors. I've done it many times including today actually when I had to replace two injectors on his little honda civic for him.

the only way I can see this happening is if the pump is trying to reprime itself or something like that and it cant which would only occur if the tank was empty.

 

If you don't have power on, then no problem, but in your prior comment you talked about cranking it up and then pulling the relay, but I think it would be better to start with the other way around in order to do that.

 

Fuel pump relay insight [non-inquiring minds can skip]:

We know the fuel pump is needed to push gasoline from the tank to engine (feed the beast and push the the fuel against gravity].

The second you stick in the key in (getting ready to start) the pump is activated. Now guess what happens in an accident? A smart unit looks for missing spark activity (spark is controlled by turning engine) and cuts off the relay and thus disabling the fuel pump.

So it should be ok to disable the fuel pump relay.

Salim