2005 Nissan Sentra takes a long time to start after running AC

If you are afraid that running air conditioning after a long trip causing over heat then have pressure test. Taking a long time to start happens due to 2 problems: 1- The cold start valve is not operating. This due to a problem with the coolant temperature sensor bad or a cold start valve itself. 2- Poor compress pressure from each cylinders due to a leakage in the heat gasket as a result from overheating due to inefficient cooling. For example using air condition on the long ride uphills on mountain...

I would recommend a thorough throttle body and injector cleaning. If you have 70K plus miles on the vehicle, combustion deposits build up on the back side of the throttle body and plate as well as the ends of the fuel injectors. When the build up is sufficient enough it will block the area of the throttle body blade that allows air into the engine for starting.
The deposits also build up on the injector tips and distort the fuel spray pattern that will cause a delayed starting problem.
Have them both cleaned along with a fuel filter change and your car will be back to normal.
Good luck.