1996 Z71 shuts off when put in gear?

If a 1996 Z71 shuts off when put in gear, it could be due to several issues, including a faulty idle air control valve, a vacuum leak, or problems with the transmission such as a malfunctioning torque converter. Additionally, check for issues with the fuel system, like a clogged fuel filter or failing fuel pump, which can affect engine performance under load. Inspecting the electrical connections and sensors related to the transmission might also reveal underlying problems. If the issue persists, it may be wise to consult a mechanic for a thorough diagnosis.