2003 gmc sierra runs but then dies and has no spark after a while it will start again what could it be?

The issue you're experiencing with your 2003 GMC Sierra could be related to several factors, such as a failing ignition coil, a faulty crankshaft position sensor, or issues with the fuel system. When these components overheat or fail, they can cause the engine to lose spark and die. Once they cool down, the vehicle can start again temporarily. It’s advisable to perform diagnostic tests to pinpoint the exact cause.