Does my2001 chev tahoe with 5.3 have a EFI cold start valve ?

No , the PCM/ ECM just turns the fuel injectors on a little longer till warm up.
The powertrain control module (PCM) reads voltages from several sensors in order to determine how much fuel to give the engine. The fuel is delivered during one of several conditions called modes. The PCM controls all modes.
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The Starting Mode--With the ignition switch in the ON position, before engaging the starter, the PCM energizes the fuel pump relay for 2 seconds allowing the fuel pump to build up pressure. The PCM first tests speed density, then switches to the mass air flow (MAF) sensor. The PCM also uses the engine coolant temperature (ECT), the throttle position (TP), and the manifold absolute pressure (MAP) sensors to determine the proper air/fuel ratio for starting. The PCM controls the amount of fuel delivered in the starting mode by changing the pulse width of the injectors. This is done by pulsing the injectors for very short times.