Sorry, nothing is "locked open." Injectors are electrically activated, and there is no electricity with ignition switch off. The injectors are opened by electrical action and closed by spring action when electrical charge is removed.

It is impossible to "pump the gas" with a fuel-injected engine because there is no mechanical connection between the throttle and anything connected to fuel. All "pumping the throttle" will do is open/close the air source. But, the engine has to be running before any more air enters, so pumping the throttle with the engine not running does absolutely nothing. It does next to nothing at slow cranking speed.