RE: 00 silverado hard starting
If your fuel pressure is within spec, start checking your throttle positioning sensor, advance, coils, and distributor. It wouldn't hurt to pull a plug and hold it on or very close to the block and have someone bump the starteer to see if it is getting good fire. I would assume it does as it still starts and I assume runs fine. I think I would bet on the advance, it should be a vacum advance but I am not sure. When you first start a car it will run rich, fuel injection runs 14 to 1 or 14 something, but to start needs to be a little richer, the timing will also advance so it will run smooth on inital start up. If your fuel air is a little rich as it should be but your timing is not being advanced that could very well be your problem.