I need some help I have a 91 camaro z28 5.7L 350 and it will not crank up for about a hour after it has been driven. The engine turns over but it will not fire up. Can anyone offer some advice.

 

by "turns over" do you mean it is cranking good and not starting or is it cranking too slow? cranking too slow i would look at starter heat soak. if it is cranking fine and just wont fire up, check for fuel and spark.

 

cranking good but it will not start after it been drive for about a half hour

 

Most likely an ignition problem. Check for spark. Could be a fuel problem, check for that if you have spark.

 

it has spark but no fuel until it cools down

 

thats your problem, you need to find out why their is no fuel. check for power to the pump. if there is power but the pump wont turn on, replace your pump. if there is no power, you need to find out where and why there is no power.

 

the fuel pump was changed but the runs good but after it run for about a hour if turn it off it will not come back on for a hour or 2

 

Sounds like a bad pump. Happens all too often.