Chevy Tahoe Intermittent Start-up Issue

I have a 2001 Chevy Tahoe, and it has close to 175,000 miles on it. I bought it used when it had 110,000 on it, but I was o.k. with it because it was a company car and the 110k were mostly highway miles. But for as long as I can remember, sometimes when I get in the car to start it, it takes either 10 seconds or so to start the car while the starter attempts to make the car start. Normally, if this happens (because sometimes it starts right up) I turn the key to start for a second or two, stop, turn it back to start again for a second or two, stop, and normally on about the third go 'round the car will actually start. I have noticed that if the car has been running for a bit and I turn it off it will start right up within about 10 minutes or so of turning it off. I have had the starter replaced and it didn’t seem to fix the problem, and wanted some input before I take it to my mechanic. Any ideas?

The problem might with the antidrain-back valve in the fuel pump assembly. This valve prevents the gas from draining out of the fuel rails/line back into the gas tank.

To determine if this is the problem, the next time you know this starting problem is going to occur, turn the ignition switch to run position so the dash lights come on for two seconds, and turn the ignition switch off. Repeat this a half dozen times and then try starting the engine. If the engine starts with no problem, the problem is with the antidrain-back valve.

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