Crankshaft position sensor bad?

Yes, a bad CPS will result in no spark. As will a bad Cam shaft sensor and a bad (striped) timing belt.

My 2000 caravan got me to work one day just fine. When I went to leave work if cranked just but would not start. Got towed home and tester said "bad cps". So I replaced it. Then the tester said "bad camshaft sensor". Hmm? That is when I noticed the distributor wasn't turning. Pulled the front of the engine off and found that my timing belt was striped. Replaced that and bingo!

My 2001 sable would occasionally crank but not start for 20-60 minutes. In the end it was a bad fuel pump.

In your case I suspect a fuel issue.

If the CPS is bad then you won't have any spark and possibly no injector pulse as well.The CPS tells the computer the position of the crankshaft for proper timing and fuel injection purposes. So if you are getting good spark but no start, then likely you have a fuel related issue...weak or bad pump, bad pressure regulator, clogged filter, bad injectors, circuit issues/bad pump relay or bad ground wire at pump, ECM issues, etc... You can test for proper injector operation/signals with a Noid light...sold at parts stores. Or verify the problem is a fuel issue by spraying a little carb cleaner into the throttle body or a vacuum port and try starting...if the engine starts and runs briefly, then it's a fuel related problem.

No spark but then the spark is good? Sorry this makes no sense

A faulty crank position sensor will always prevent the engine running as no spark will ever happen and it will probably not inject fuel even.

The CPS has taken over from the old marks on the crankcase and flywheel. It detects when no. 1 cylinder is at xx degrees before TDC and initiates the spark.

What car?