Ok this is pretty strange. I was at the gas station getting gas in my 1990 Iroc, and when I tried to start my car, it was cranking, but not starting. I think I was getting fuel because I started to smell it after a little bit. But after trying over and over for about a minute, she fired right up and drove like a dream again. This has happened to me once before about 4 months ago.

Now, here's my prediction, and you can tell me if you agree or not: I have a problem with shot valve seals, and I think that the oil is dripping down and coating the spark plugs, preventing them from igniting the fuel. Make sense?

Anything else that would cause a problem such as this?

 

That is possible, but not likely to happen in the time it takes you to get gas. Theres a way to check it out though. Just pull off a few plugs. If they are covered in oil, then theres (at least part of) your problem.

Since this problem only happens once in a while, I would guess it is an intermittent fault. Problably a loose wire somewhere. These are really tough to pin down.

 

your problem dosent sound like valve seals to me,my first guess is a defective fuel pump relay, can you hear the fuel pump power up when you turn the key on. if not, after you crank for awhile and estibilish oil pressure then you activate the fuel pump and presto the engine starts, since your problem seems to be intermitt then i would suspect a wiring prob.
by installing a fuel pressure gauge to your fuel manifold you can verify what you fuel pressure is when you first turn you key on......good luck

 

right,no way "leaking "valve seals goingto cause that problem....even if you had no seals at all on every cylinder i doubt it would leak enough oil in a short period like that to foul up the cylinders to the point they couldnt fire.
if you has a smell of fuel look to the ignitionas a cause.dont look under rocks you know aint holding crickets