I replaced the crank shaft and cam shaft position sensors, but still after a drive when i turn off the the engine and then try to restart engine it cranks,(no movement from rpm gauge) and takes a few seconds 2-4 seconds to start. What else could it be?

Almost sounds like your loosing fuel pressure. Try to prime the pump 3 or 4 times before you crank. ( Key one key off 4 times then crank. ) When it’s running does it have good power? Try getting on the high way and holding it wide open throttle till you hit the speed limit. Clean mass air flow check spark plugs make sure no oil is in the tubes. Check connection at the coil packs.

I’ve had this issue for a few years now. It is almost certainly a fuel problem. You have 2 options if you don’t want to fix it.
1. Turn the key to the on position for a few seconds before trying to start the engine. This gives the fuel pump a few seconds to pressurize the line. (This is my preferred method).
2. If you’ve already started trying to just turn over then engine, and it is just sputtering, turn it off for a few seconds. Then while you are trying to start the car, floor the gas until you hear/feel the engine engage. (This is an old school method used on non fuel-injected cars, but for some reason it also works here).
3. Pay someone more than your car is worth and your right leg to fix the fuel line.

Try getting oem sensors. They can be troublesome.