The 318i is a luxury compact car manufactured by BMW. While the vehicle comes with several automotive features, none of those features include a sure way to start the car every time. Luckily, the causes for a BMW 318i that won't start can usually be narrowed down to a few common problems.
Out of Fuel
The car may simply be out of gas. Don't reject this option as foolishness. A common cause for a car that won't start is something as simple as an empty fuel tank. Check the fuel level of the fuel tank and try to start the car again.
Depending on the model of your 318i, your BMW may be equipped with an antitheft system that is preventing your car from starting. This could include a smart-key option that does not allow the car to start when you use a duplicate key.
A dead battery is another common cause of a no-start engine. Try jump starting the battery with another car. If this does not fix the problem, purchase and install a new battery.
Clogged Fuel Filter
The fuel filter helps get clean fuel to the engine; however, if your fuel filter is clogged, this can decrease the amount of fuel actually reaching your engine. An engine with no fuel won't start.
The starter is a component of the ignition that works to ignite the fuel-to-air mixture in the engine. If the starter has gone bad, your engine will fail to fire. Try opening your hood and inspecting the spark plug. Look for corrosion and faulty wires. Make sure the starter has a clean connection.