Modern cars are not hard to troubleshoot

All cars; new or, old. follow the same laws of physics.
fuel+air+electricity=running engine.
So; first we look for fuel: there are two ways to do this: while turning the key to run
lean out of the driver's seat and, listen for a short 2-3 sec. buzz; this will be the electric
in-tank fuel pump starting up, holding pressure and, shutting off to wait for a demand for fuel
if you hear this the fuel delivery system is good.
Next; we look for; spark (electricity) the only safe way to troubleshoot modern computerized
ignitions is with a inductive timing light; hook the timing light power lead clips to:
the car's battery: red to the positive post and, black to the negative post; then: take
the inductive clamp and, hook it around a spark plug wire; any wire will do:
crank the engine and, count between the flashes a four cylinder will flash either every time if the clamp is on a main lead or, once every four times the engine rotates again. of course the count is: six for a six cylinder; eight for an eight etc.
No spark? ignition has failed. Next: air in the intake of your car is a small flap attached to a switch; open the intake and, crank the engine while spraying starter fluid (ether) into the intake engine starts then dies; fuel filter failure; no start: flap switch failure (no fancy names here)
engine runs replace air filter. of course this doesn't cover everything sometimes even we
mechanics get stumped; but, this should at least prevent you from not spending a fortune to
fix your car