My hummer sometimes will not start like it doesn't want to fire up. Wait 10 min and it starts.
I would say the fuel pump is a good place to start. sounds like its not building up good fuel pressure.
to test the fuel pump/filter, have the truck off, then turn the key to acc/lights come on, but not the engine, some models you will hear a low gurgle sound, for a few seconds, turn the key off, then repeat the process again, then off, then start it, to see if the system is just needing more pressure to be primed...
My 2006 hummer h3 is doing the SAME thing, did you find out what was wrong with yours??
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