Car turns over but won't crank?

Fuel pressure regulator may be going bad. It's supposed to hold pressure in the fuel rail while the engine is shut down. When cranking, the fuel pump has to build pressure again before the injectors will properly inject fuel. Try turning the key on (without cranking) for about five seconds, then back off. Do this two or three times, then try to start the engine. If it starts right away, you need a fuel pressure regulator. These can be located on the fuel rail, or in/on the fuel tank.

When it fails to start-- do you have spark or injector pulse or
fuel pressure-- while cranking--?

Could be a crank sensor --but replacing parts with no testing,
is not the way to go --learn how to test components

Could be a crank sensor failed, fuel pump or timing issue,
chain or belt whatever it has

Look at Professional Scan Tool Data--codes or not, that is
always where you start & check the battery out is always a first
step as well

If you have a vats system (anti-theft) it needs to be reset

are there any codes? have you checked the pressure in the fuel line. you may have a bad fuel pressure regulator. or a bad crank position sensor. spray starter in the throttle body and see if it starts

It might not have enugh pressure to run at all. Try spraying aero start, start ya ******* or similar in the intake & see if the car runs with continual short bursts of spray. If so it is a fuel problem. you can also try to crimp the fuel return hose with a pair of pliers but this will only increase the pressure if the regulator is stuck open not if its a faulty pump

Done cars have a kill switch if they are low on oil. Check your oil. If the oil is good, it may be the ignition switch.

If the engine fires up for a second or two with starting fluid then the fuel pump is weak.I would check the fuel pressure and if its not within the specs then replace the pump and filter.

starting fluid is a thing of the past. dont use it. this car doesnt have a carb, its a throttle body/ electronic fuel injection system. you most likely have a fuel pump or fuel pressure regulator issue. test the fuel pressure, should be anywheres from 35-50 psi

spark pug gaps are critically important & can even stop a car from starting! start there!
then reset the timing!
computorised cars should be banned! lol

you might have a bad manifold absolute pressure (map) sensor. it's on the intake manifold, it weighs the air that comes in the intake (weird huh) and if it goes bad it reports a condition that doesn't really exist to the computer that controls engine functions. if you unplug the sensor and then the engine starts, you got a bad sensor. the engine computer will set a code and the check engine light will come on, but you can replace the sensor and have the code cleared. if you unplug the sensor and the car still won't start, it's not that sensor. hope that helps. failure of this sensor will definitely cause a no start condition.