I have a 1994 2wd S10 Blazer. We were told it has a recently rebuilt engine when we bought it. Runs great except for a starting issue. If you go out in the AM it starts right up no problem, but drive it and shut it down and try to restart it starts hard. Cranks and cranks but always starts. Recently it did this and it almost didn't start, it was much longer getting it to start than usual. We were told to check the engine ground, checked and no problem there. What else could be causing this? TIA

 

If the starter is cranking the engine just as fast as it does when cold, I'd start looking at a fuel system problem... either the fuel pressure regulator at the front of the intake manifold, or a fuel pump on it's way out.

 

I had that problem on my 92 sonoma once, it turned out to be the engine temp sensor, it would bust off fine cold, but when it was warm the computer was giving it too much gas thinking it was still cold, basically flooding it out, I tried everything, plugs, wires, o2 sensor, that was the last thing I changed and it fired right up when I changed it.