Just turning the key to the RUN position does not start the fuel pump (unless your AFM is bad), so it can't be building up pressure until you crank. Yes a lousy fuel pump could mean a little longer to build up the required pressure for injectors to atomize, if the fuel return to tank is too large.
But to find out, you need some tooling to tap in the fuel rail and monitor pressure.
But to find out, you need some tooling to tap in the fuel rail and monitor pressure.
