A 3 days ago i went out to start my car and it wouldnt start. it had sat for 4 or 5 hours and when i tried to start it it could crank and everything but just wouldnt start. but after 3 of 4 turns of the key it finally started, that happened the next 3 or 4 times i shut if off but then everything went back to normal and it was started fine until this morning. This morning i went to start it after it sat for 8 or so hours and now im having the same problem, it cranks and cranks but never starts.
any ideas what could be causing this? i just changed the starter a couple weeks ago as well as the battery and alternator.

We need to know if it is fuel or spark related. If it won't start, check to see if any of the spark plugs are getting spark. If they aren't I would suspect you need a crank shaft position sensor. If you are getting spark rent/borrow/steal a fuel pressure gage and see what the fuel pressure is with engine off key on.

The fact it is cranking indicates the problem is not the battery or the starter.

ok ill check those out and let u know the out come, thanks

I jsut got dont checking the spark plugs and there not getting any spark.

If you aren't getting spark to the plugs, the first thing I would check is the CPS (crankshaft position sensor), located behind the crank pulley. It'* a pretty common fail point for many GM models, as it is subjected to heat and debris. It'* also a common cause of stalling when hot, or hard-to-start when hot, but as the sensor gets weaker it can lead to an intermittent no-start problem.

The crankshaft position sensor tells the computer the engine is physically turning, and tells the ignition module to produce spark. If the ignition module doesn't get this signal, it will not send spark to the plugs. You will most likely have to remove the serpentine belt and vibration dampener (rubber-filled pulley on the crankshaft) to access the sensor.

If you're replacing the crank sensor, you might as well splurge for the vibration dampener (harmonic balancer) as well - the dampener on my '87 LeSabre went, and I splurged for the CPS as well since I could get to it easily with the old dampener off. And, like I said, it'* a common fail point.

Hope this helps you out; if not, we can troubleshoot further... Ignition module or coil could be bad, but that would be The Next Step.