The car : 97 altima gxe made in the usa 5/96 manual trans , without anti-theft
have a wiring issue, its possible i have damaged ecu.
after replacing fuel pump still no fuel. wire harness at the fuel pump connector had 12volts, so i replaced the pump , now there is no voltage at that wire harness. i have already run wire from battery direct to a switch to fuel pump, pump works, where i was going to use the original fuel pump wire harness to activate a relay now that won't work because no voltage there now.

So now i have a switch instead of a relay, i CAN run the vehicle this way but, i read on EC-17 of the 97 altima fsm " Fuel shut-off : fuel to each cylinder is cut off during deceleration or operation of the engine at excessively high speeds. " on EC-20 it describes more fuel cut off, but states its different from whats mentioned on EC-17. without a relay the worst i think could happen is i waste gas on decel or forget to turn the switch off(correct me if i am wrong ).

but my actual question is : does fuel cut off mean A: the power to fuel pump is cut off. or B : the fuel injectors do not open.

If anyone knows of any reason why I shouldn't wire from battery to fuse to switch to fuel pump or knows about the fuel cut off please reply, I thank everyone in advance for your time and assistance.

Mods : i made the title more general than " what does fuel cut off do ? " in case some one wants to warn of some unforeseen danger in my wiring, but feel free to change it.

The pump doesn't shut off at decel, the injectors do.

There are all kinds of fire issues involved with using a switch on fuel pump. Leave it on and engine off with a leaking injector and you hydro-lock the engine and new engine time.

You can wire pump to ignition switch and get rid of some issues but not all. Just not wise at all to do it.