Okay, here is the problem. I have a 91 Z28 5.7. It runs fine when you crank it up cold. It starts right up. I can get in it and drive it. It will idle fine at stop lights. It never has any hestiation and has plenty of power. Once I stop and let it sit for 5 to 10 minutes it will not start. It will crank over fine. The car never got above 160 degrees. Auto Xray numbers look good. I have replaced the fuel pump with Walbro 255. I have replaced the module in the distributor. I have replaced the coil and still no luck. I replaced the computer. Any ideas. This is really killing me. The VATS light comes on but goes off in two seconds. The alternator seems to be charging fine. I am going to try a different battery tonight. Any ideas and suggestions? Thanks, BranZ

 

I had the same problem, It was heat soak on the starter from the headers.

This fixed it forever Heat shield

 

I had that problem. I didn't think it was the starter because it would turn over fine. I just had to crank it forever before it would fire. It turned out that I had a couple fuel injectors that were leaking. I replaced them, and the problem went away. See, while the car is sitting, the cylinder is just getting filled with fuel. So, it is just like starting a flooded car. Hope this helps.
Fbird

 

I just do not understand why I have the problem after the drive. The car cranks up cold with no problems. You almost can not get you hand off the ignition fast enough. Performance is excellent. The gas mileage has not been the best but I just run it up and down the road. This problem started when I put in the used LT1 injectors. I hope this is not the problem. Any other ideas?

 

like fbird suggested, get your injectors examined n tested.

 

When it happen to me, the car ran fine. It had good responce, and no problems starting it in the mornings. But, if you let it set for a couple minutes, it would take forever to actually start. There are a couple things you can do to check them. That is where I would start. Sounds like you have eliminated everything else.
Later,
Fbird

 

posted by BranZ
Sounds like the injectors to me.