2002 Avalanche, Z71, 5.3L (purchased new June 2002)

I love this truck! I just past 90,000 miles and I am still not tired of her. But, the old girl is having some minor age issues. I'm still going to keep her though. I hope you guys can help out a little bit.

I live in Arizona. Was in Phoenix, now in Tucson. One thing is still true in both cities, it is hot. So, my Avalanche starts almost immediately when cold. But, when the temperature is about maybe above 80 degrees, cold start, I can crank all day and the engine won't turn over the first time I turn the key. Also, when the engine is hot and sitting for more than 10 minutes or so, the same thing...can't start on the first key turn. But, if I just bump the key for a second or two, wait for a couple of seconds, then crank again...the engine starts immediately.

I think it may have something to do with the electric fuel pump or fuel pump relay since I don't think I hear the fuel pump cycle when I turn the key the first time. But, the fuel pump definitely cycles when I turn the key the second time.

Do any of you guys have any ideas about what is going on?

Thanks,
Jenny